The good news is the new relay from Napa showed up the next day and it works perfect. Both sides of the relay (87 & 87) turn on and off at the same time and the car no longer has a draw. Somewhere someone tied those two circuits together though. However, the customer claims the car has not been to anywhere, but the facts are the facts, and we know that is not true. Needless to say, I double checked to make sure each circuit is still fuse protected independently and they are, so I left the whole mess alone. On to the next one! -Eric O.
Oh damn, spoiler alert, no part 3. I should've read this before posting, but I like to post before my thoughts evaporate, which seems to happen a lot quicker these days. Anyways, you kinda spoiled the thriller ending. BTW, get a laser printer, even a colored one for most of your printing needs and you will end most of your ink issues. Yes, they cost more. Thx for packin us around and givin us the scoop.
Now it working better than factory....Now both 87 contacts draw each half of the total current, say 2 times 7A (=14A) instead of 1 contact doing 10A and the other one 4A, also totalling 14A. 😂 Less chance that the "10A" contact one burns in. Now, both are sharing the load.😂😂 😉
Looked at the video from 9 months ago and your right that relay back then was white in color not black , love your diagnosis and how you double check yourself and your process , man i wish i had a mechanic like you close by , love this channel
Not only is there a different relay in the original video, the wiring harness has the original hyundai wrap instead of the electrical tape shown in this video. And I learned a little bit about relays today.👍
The thumbnail of your original video on this car clearly shows a different relay in that spot. Someone was definitely there after you, looks like they fixed it until it was more broken. I totally understand that feeling when you just gotta know how something is working when it clearly shouldn’t. Great diagnosis, as always 👍
The thumbnail shows the white Hyundai relay as shown in this video on Eric's computer screen. It stands out vividly, and is clearly _not_ the black one seen in this video.
Super funny before I even read the comments I went back and looked at the other video and saw that it was a shiny white relay not the one that he pulled out
Yep, today I learned the importance of paying close attention to the pin numbers of the relays. I could have easily made that same mistake in the past.
i get confused with red & black.. back in 70,s. id fit relays for spots ect. no prob. now i have to have diag & do slowly, . 67. sik of learning tech sht.. ausie..
There are basically 3 types of relays: SPST, Single pole single throw, one action, one result. ON, terminals make contact to energize one circuit. OFF, terminals disconnect. DPDT, Double pole double throw, 2 actions, 2 results. ON, terminals make contact to energize one circuit, OFF, terminals connect to energize one other circuit. DPST, Double pole single throw, 2 actions, 1 result. ON, terminals make contact to energize 2 circuits from one feed. OFF, terminals disconnect. Same theory of operation for different switches. Fantastic find, Eric. Most techs would have missed this completely and not investigated the relay. Whoever did that to the relay probably thought they were only connecting the two outputs to tie them together, but they actually made them live in BOTH conditions. they likely didn't check the circuits when the car was KOEO. The very definition of knowing enough to be dangerous. Most likely the reason for the DPST relay is because the amperage of the relay can't handle the load on a single pin, so it's split between two pins to share the load. Most relays can only handle a max of 30 amps, and that fusible link is 40A. Longevity is the reason for the DPST relay, even though a SPST relay will work for a short period of time. While the two circuits are independent, it's only on the output side of the relay that they are independent. They are fed from the same source, so when the relay is in place they are tied together. When the relay is out, they are independent. Again, it's for amperage rating and longevity.
Looking at the wiring diagram (if you can trust it) the factory engine control relay is a Single Pole Double throw (SPDT) relay with Normally open contacts . When the relay coil is energized the relay closes the two open poles thus allowing power to come from the 40 amp fuse through the switched legs out the 2 separate poles.
_"DPDT, Double pole double throw, 2 actions, 2 results. ON, terminals make contact to energize one circuit, OFF, terminals connect to energize one other circuit."_ This isn't correct, if it has two poles it has two circuits. You are describing a single pole double throw, SPDT. The Hyundai relay is a DPST with one side of the contacts commoned.
I had to go see for myself. It’s pretty cool the act of making a TH-cam video provides the evidence that clearly shows that relay has been changed between that fix 8 months ago and now.
I would call that relay a normally open double pole single throw relay. Dpst. Awesome video. I am a HVAC tech. I watch your videos because Your electrical diagnostic skills can also be applied to HVAC service. So thanks keep up the good work.
Someone did a whole bunch of extra work to avoid replacing the relay with the correct one. Maybe they were in a pinch and couldn't get one? I bet that story would be an interesting one to hear. Thanks for the video!
Eric, you had me cracking up so much with your comment, " somebody had there beaters in here" Your one in a million, thanks for all your hard work. Take care
I had this conversation with my students about a relay with two 87 pins. They are also used in some am light circuits use this type of relay. Power in 30 and out to both lights. Great video
Run into this with some of the European manufactured equipment I have the "privilege" of working on time to time.. Screws even the most "schooled" of been to this or that education system DIAG Eelekchiken..
shouldnt a split relay, have different draws, hence 2 curcuits..???. seems a cheap way of elliminating a relay. plus, if one powers 2, curcuits, & blows a fuse, then you have more sht to go thru.. dmb ausie here..
Mrs O has the right attitude, it's broken, so no harm in trying to fix it. They'll try to sell you another new tank either way. Especially when things are out of warranty, you have even less to lose.
I wonder if it was a manufacturing option where the same base was used for multiple configurations with maybe a link between those two contacts as an option. But then again, the two circuits coming from it would make that a weird thing to do. It does hint at someone bridging them because of an issue they caused by using a changeover relay. If it's an ecotank printer, a full waste ink reservoir would stop everything working. Depending on the model the new easy-change ones are chipped so it knows it's been changed. On the older models you need to buy a sneaky reset key online. There are also non-manufacturer-approved ways of cleaning very clogged print heads involving low lint kitchen wipes and glass cleaner. There are videos of that on TH-cam.
We had that printer for many years. Actually surprised it later this long 😂. Vanessa bought another one to replace it. After reading comments I guess we should have went with the colored laser printer. Next time 🤷🏼♂️
So the correct relay is a DPST with common single feed and some one installed a SPDT. Gotta love that! As for the circuits being powered due to the "beaters" splicing, depends on where they made the splice. If they made it before the individual loads fuses - then not really a problem (as long as you note your diagnosis) But if they made the splice junction after the fuse, well now you have a big potential problem. Because now you have a fuse protected circuit at 20 A may now have 40 A serving it, this could end badly down the road. Getting back to comment about service information lacking, I feel your pain Eric,,,, I feel your pain!
Yes, I was going to say the same thing. The OEM relay is not a double throw relay because when relay is off current goes nowhere, there's nothing hooked to that side. It's a double POLE, single throw relay with the unique feature being common feed to the two poles tied upstream at pin 30. Swap that for a standard SPDT and you've got power going to one arm with key off, where 87a connects. As Eric points out, the mystery doesn't end there because of what he found when relay was completely removed. I like the theory that instead of realizing what was happening, another mechanic jury rigged a downstream connection, not understanding that the wrong relay would also cause a parasitic drain. Hopefully he did that upstream of the fuses. That other mechanic might have noticed that the other arm was not powered up with key on, which might have thrown all kinds of diagnostic codes if the car ran at all. Maybe he thought the problem was in the fuse box rather than the simple explanation of wrong relay.
@@spelunkerd Absolutely! My guess is that by fixing the original problem (relay) the wrong relay was installed and the mental connection did not register so the next fix was to meld the 2 circuits together. I have seen something like that many times over the years. As we both noted, lets hope the joined connection is before the individual circuit fuses and not after.
Consider the problem Eric O found - the relay was stuck closed at all times. The original, double pole relay, split the load going through the relay into two poles (both fed from the same main 40a fused supply.) The fact the relay was replaced with a single pole relay (probably rated for 30a,) and the two loads tied together at the output, now put that entire 40a fused load through the now single relay load path. I suspect that's what made the relay fail. I don't suspect the downstream circuits have any loss of protection, just now the relay load path is all forced through one path not rated for it.
@@ablackformula The fact that branches were fused downstream gave the false impression that the relay had failed, but the story is more complex. That incorrect single pole double throw relay when functioning normally offered a pathway through 87a when the key was off, and through 87 when key was on. So, although it looked like the relay was bad, it wasn't bad and it didn't fail. It simply didn't belong where it was being used.
Thanks for the video. This has been so informative for me. I have saved every fuse and relay from every car I have donated to the fire department. I have never thought that the relays could look the same but be different. Thanks again for explaining the processes you go through.
Wish SMA was a bit closer to my home. I live about 450 miles away but would consider the drive if my vehicle would make the trip when it needs servicing. Every time my wife hears your voice Eric, she always says are you watching your boyfriend again lol. Great work Eric as usual
I'm thinking that after the last 'mechanic' replaced the original 87-87 relay with the 87-87a, they didn't understand why the circuit on 87a lost power with the key on, so they 'fixed' it by jumpering them together downstream of the relay. Weird that Hyundai used that 87-87 relay though. All the power still needs to flow through terminal 30, so it's not really increasing the current rating. They must want to isolate the 87 and 87a circuits when the key is off. Maybe there's some backfeed issue?
Yup that's what I think as well. I replaced the relay but now some sensors don't work any more, screw it just jumper the two together and get it out of here.
I think the bottleneck in the relay isn't the terminals themselves, but the contacts. The contacts can only handle so much current, so this was their way of using 1 relay as functionally 2 relays.
I think that the main issue is the contacts in the relay, making them large enough to carry enough current for two loads would necessitate making them heavier, thereby requiring changes to the mechanical operation of the relay, potentially increasing its size, etc....complexity
Holy crap, I don't think I've ever seen a dual throw 5 pin relay until now. Or like you said, that style of relay might have been used on the vehicle I was working on and I just didn't know. Regardless, this was a terrific video and I learned something as usual. Thank you very much!
I've never seen one either. If it was a late 80's or early 90's Ford Mustang, they decided no relay was needed at all for the headlamp circuit and didn't use a heavier gauge supply wire than any of the others. They had a TSB but no recall. Likely the Chief Engineer who signed off was mechanical not electrical.
It's a double _pole_ , single throw relay (with one side of the contacts commoned together). Don't mix your poles and your throws, you might offend a Polish person 😀
Hey Eric, so its really funny as I am watching this video, this was actually a test we had to do in Transit when we get promoted to mechanic or if you come in brand new, in the training school our electrical superintendent or the instructor lol. He actually used this example for a test, so he replaced the relay with a different relay so that the power would stay on the entire time, we had to diagnose why there was battery draw and why it was killing the battery. So we had to go into the electrical system and test and figure out what was going on, and the issue was exactly that a wrong relay which kept power on and when one of our guys pulled the relay he actually went and grabbed another relay of the exact style and we continued to have the issue, and it stumped everyone in the class not understanding what else could be the issue and when I checked the entire wiring diagram I saw exactly that, it should be switched off when the ignition is off and switched on only when the ignition is on, so I checked the relay number against the wiring diagram and bang figured that issue out right away. It was fun to learn these types of things because they not only apply in this situation but also can apply in a real life situation such as your video. It's crazy how many "Mechanics" would mess this up by putting the wrong relay in, so yeah definitely shame on whoever did that. I love your video's thank you so much for them all!
Like the behind the scenes thought process! Very informative! Especially the internet mathematics! "What did we start out making this video for?" as you're grabbing your test light, absolutely hilarious!
Thank you for showing us an example of a work around that has existed since they started putting the fancy little boxes in our cars❤ Sometimes, all we think about is, there's no place like home, we will deal with it if we ever get there.
Great diagnostic, Eric! My view is that, somewhere along the line, someone replaced the relay but didn't have one with double-throw contacts and tied the two circuits together. This would probably overload that single contact (otherwise, factory wouldn't use a dual contact). Now, with the correct relay, it doesn't make any diference, as curent can go through two contacts again.
Things like this make my head explode, good thing there's guys like you that can think through it and make sense of it so guys like me can relax knowing Eric's got this.
Just worked on a Hyundai Genesis Equus earlier today. Instrument Cluster was completely black. She thought she needed a new one and ordered it for me to install. Fortunately it was an easy fix I just reset the memory 30 amp fuse. Cheers 🍺
I guess my concern would be if the wires are tied together after the fuse, you might have a wire that's only rated for 15a tied to a 20a fused circuit . Witch could be a fire hazard. Awesome diag as usual!
EXCACTLY WHAT I SAID, & I KNOW SHT.. ausie.. dpst relay, seems a way to have 1 relay do 2 jobs, but then, your fuses blow & twice the pain to konw whats wrong..where..
Okay, If that relay is powering both circuits, then you should be able to control those circuits with a 4 pin relay as long as the power, ground, and control pins match the fuse box wiring. I believe that the pins on that 5 pin relay do not have the same configuration as the original factory one. I had problems similar to what you are finding on some of the BMW's I used to work on. Great diagnostic work. Thanks.
When I started off at my first dirt assignment after a year in school one of the sergeants came up and handed me the largest flat bladed screwdriver and said this is a “one level” you can work on anything it fits. As time went on you were allowed smaller tools to utilize working up to a “seven level” in the field which was a plastic tuning wand with the metal inserts. In electronics you could do the most good or bad with the smallest of tools. Component level diagnostics were required. Mr. O hands out the tuning wands…
Good find. I know it’s not correct, but you could have fitted a standard 4 pin relay just to test if circuits were tied together. Thanks once again for sharing your day and keep up the great videos. 👍
Very valuable video. About half the population purchases used cars. These vehicles are being sold for a reason. Something exactly like this may be one reason.
You should definitely get a color laser printer. No going back afterwards, fast and reliable. Reasonably priced nowadays too, I recommend something like a Brother HL-3220CDW also, quite the gaming rig for Mrs. O!
for temporary test, put a jumper from "87 to 87a" then insert 4 pin relay (or use fancy external jump tester) to do the same thing. but very probably smoked wire harness and shorting out underneath the fuse box/elsewhere also.
I was on the edge of my seat for the entire video with my head spinning. Most impressive on your thought process and diagnostics, as usual. Good work. Electrical issues for the most part are not my favorite repair jobs. I don't have the equipment as you do or the extreme knowledge. Perhaps in my next life I will be an electrical engineer!!!! 🦉
I understand less than half of it, and still find the analysis fascinating. Often he explains it so well that I do get it, as a complete armchair mechanic. It's like watching Big Clive explain electronics. He's in the comments, by the way.
Very good find Eric O! Proved you can't always just stick a like looking relay in place of another just because they are the same size and have the same number of 5 terminals. Must go by part numbers when comparing like size and looking relays. That is why they have part numbers on them and the spades are numbered. Somebody set this trap up for failure and you were smart enough to catch it. Thank goodness for wiring diagrams or you would have never knew about the double 87 relay.
My service truck uses 3 relays to cancel the PTO from being switched on depending on if the air brakes are set, the rpm’s are at idle etc. I was looking at them as my PTO wouldn’t turn on and two of them are tan and one is purple, the Orielly’s cross refrence for them is the same but the purple one is normally closed while the tan ones are normally open. It ended up being the air brake switch but I can see someone not paying attention and putting an Orielly’s relay in there that’s wired backwards and the pto wouldn’t ever work. Great video, never assume you’ve seen it all.
I see someone has had there fingers in there messing with things. There are many types of relays about so make sure that you change the same one that is already fitted .providing that someone has not fitted the wrong one to start with .. This does not follow the wiring diagrams so you do need to check it out for yourself so you know what the problem is. Make sure you let the customer know to cover yourself 👍👍👍
Awesome. Love stuff like this. I just fixed a car with 78 miles on it, missing fuse for the wipers and the same rating spare was also missing. There is a place where all the automotive gremlin answers live, but we'll never find it.
The relay that was in there was a Single Pole Single Throw (SPST) relay. The "87" is the normally open contact and the "87a" is the normally closed contact. When the relay is not activated, the circuit is connected to "87a" and when activated, it switches to the "87" terminal. The "87" "87b" is a Dual Make SPST with two normally open terminals 87 and 87b. The Dual make SPST relays are used to power two circuits at the same time that are normally isolated from each other as shown in the diagrams. Either relay will fit but only one will work properly.
Well done once again. I especially liked the "If I can do it..." part. "Well, some of you can..." ;) I know those little relays have been the cause of a LOT of incorrect assumptions when Shadetree Inc. starts easter-egging relays.
Eric. Relay contacts have a make and break current rating. Sometimes engineers will split the circuit between the two contacts to stay within the contact ratings. This is also important if any of the loads have capacitors or incandescent light bulbs which cause a large current spike when the contacts close. The current switched can also reduce the life of the contacts. Depending on the loads, it can be a good idea to split the load circuit becase you cannot always count on the dual contact poles closing at exactly the same time (within milliseconds of each other) where all the funny stuff happens. One contact could take all of the load for a split second degrading its life. There is also contact bounce but that is a little deeper consideration. Great Video
What they did would have worked if they had used a four pin relay, there would have been no fifth pin to keep the other sensor circuit live so no current draw. There must be a reason why Hyundai use a double pole relay in the first place so I guess sooner or later something would have failed!! Glad you got there in the end, as half way through I was shouting at you Eric, It SHOULDN'T WORK I even paused the video to look at comments to see if anyone else had spotted it, then watched the rest and then you tumbled it. Thanks for a great video!! but then I enjoy all of your postings I take away something from every one.
Excellent work. Not just a top diagnosis, but then to think "hang on a darn minute. I fixed it, but it should have been more broken before" and query that. I doubt many of us would have thought any more about it once fixed. But we really need a follow up. How'd Mrs O get on with that printer? If she got that thing going again she might need to put up a video herself. She could title it "After the other guy spent hours fiddling about, here's the real fix". 😉
The relay bit was new to me... a current draw, not caused by a faulty component but for a relay 'hang-up'. Could be useful as I do most repairs myself. Thank you.. Could possibly save me some money! 😎👍
Trowing in a standard 40a 4 pin relay in place of the 5 pin would have fixed this car...at least for awhile. However, since we don't know what the total current is of the 2 combined circuits, it may be overloaded. The manufacture put that double pole relay in there for a reason. I love these videos where Eric seemingly gets everything figured out and it looks like the video is about to end, Then something goes off in his head, and he starts thinking out loud because something doesn't make sense. Now we get another 20 minutes of video.
Nice job Eric. I love how you verify your work and make sure its all 100% correct! I recognized that Hyundai by that gcustom Napa ground cable you installed on the shock tower right by the fuse box. Yeah someone was definitely meddling around in that electrical system clearly evident by the hack tape job on the wires in front of fuse box. Ink jet prinnters are s pia, maybe its time for a lazer printer - its a business expense, treat yourself & Mrs O!
Great video as always! Went back and rewatched your video from 8 months ago. Somebody definitely swapped relays after you worked it. Love the troubleshooting vids!
I was busy typing a comment asking how the hell that car runs and then you started to mention it in the video 😂😂. Hyundai really like weird relays just like the white mini relays which are just jumpers.... who remembers that video ? Awesome and entertaining video as always...................SWEET GAMING RIG BY THE WAY
Amazing diagnosis. I work on my own vehicles and only have my own brain to figure out what I may have previously done.... don't have the issues of what someone else did. You, on the other hand, need Sherlock in your head when you open the hood. I would have never found that incorrect relay. Especially since it looked at least in color and appearance like its neighbor. Nice Job!
The reason for the two circuits is the current rating on the contacts - you want the contacts ratings to be higher than the fused legs off each. They also saved the cost of an extra relay and created a planned obsolescence checkpoint for owners.
Love it, I've only seen something similar years ago with a Mazda 3 that had a bizarre draw that shouldn't have been there from what I gathered was a stuck relay. Replaced the relay with a factory one and the draw was gone but it was a 5 pin and the harness had been touched by another shop much like yours. Never went to in depth with it as the draw was fixed but now you've got me thinking 🤔
This channel never fails to A: teach me something new (Eric is my Jedi Master though he doesn’t know it); B: make my brain connect on all cylinders; C: help me forget about life for the length of the video. It’s crucial to my and many others existence. You just need to accept this Eric and give yourself a pat on the back.
Would love to see more "off on tangents" videos. I thought I was going crazy and my wife was giving me odd looks when I was talking to the TV.. "how wasn't there any codes?", "how did this thing even start?", "why do I not understand what's going on??".
Retired from the automotive scene in 2019. Never underestimate an idiot with some electrical tape and a knife. Some of my best horror stories on cars have been a result of their meddling. Some of my best horror stories have been the result of trying to undo what some backwood in reds have done. Always remember we have to have these idiots in the world because where would we get our stories from and who would be talking about
Different relays can have wildly different internal current carrying specs, too. Since original was driving two separate loads, internally it may have a higher current rating than the Mopar one. But spec sheets would bring that to light if they could be found. There must be a reason to keep the two loads on separate wires also, just tying them together and using the Mopar part could very well cause the one leg to get too hot. You are right to get the correct part and (in my opinion) you should disconnect the two wires again primarily to prevent future possible confusion but obviously that's time.
Hi. The outputs from the relay probably got joined to get the engine to run with the remote start system. If you pull the fuse from one side of the relay output it will still have power on both sides. Cheers MD
I've been watching Eric's videos for years, but i am not a mechanic or have any training on fixing cars. I enjoy watching him troubleshoot and determine root cause. He's funny too. What i dont understand is why wouldn't the owner tell Eric that work was done on it since it was last at his shop? Overall, why aren't people honest about that stuff? I struggle to understand why people would withhold that info. What's the harm to the customer? They must know that info would be helpful to Eric, no? I can imagine this is incredibly frustrating to mechanics.
That's a new one. A lower amperage split (87 - 87) relay and 2 independent circuits on the relay load side. If all the load side was on one side of the relay, that would require a special and more costly relay. This way you can use a relay already designed and in production already at a cheaper cost just by adding two wires to the circuit which is cheaper than that special relay......PLUS the 2 pole 87 - 87 can be used as a light weight diagnostic tester already in system due to the 2 pole output for the 2 circuits, if one had a problem. Ya, I know, "That's a stretch!" Anyway, hope the new relay solves the problem. No known reason the old relay was removed, other than shot gun diagnostics? Good one Mr. O. Nice to see Mrs. O again. Where's your cat?
This time of year with the super cold here in upstate NY, Iv'e run across many battery/alternator changed by others with the same battery goes dead issue.However, you discover the customer only drives 3 miles to work and back. Not enough recharge time for that cold battery. I have fixed many by just giving that poor battery a pep up charge.
A couple of points from an electronics perspective: 1. The reason the 87-87 style of relay is used is so that the current is split between the relay contacts. The terminals are probably rated at 40 A, but the actual contacts will have a lower rating. 2. The disadvantage of the current (hacked) configuration is, if you get a short, it'll blow all three fuses, not just the one on the circuit that's faulty. This isn't a safety issue, it'll just make it slightly more difficult to diagnose.
I think you nailed it. Too much load on one set of contacts. Probably why the other 87a relay failed and welded its contact together. Wouldn't doubt this comes back in the future.
Why don't they design two independant relay's ?? Less confusing, less everything, standard parts, yes, one-more-part, and the space and wiring for one more relay,... but I see more negatives than positivs,....
@Discretesignals It did not weld itself together. It was on the dead pin in the powered off state. But because of wherever they put the jumper, it powered the circuits from the other pin that would be hot in the deenergized state.
A quick test to show the circuits had been joined would be to pull all 3 'sensor' fuses and then see if the two 87 contacts in the relay socket were shorted - the oem diagram says they should not be. My bet would be a link either on the back of the fuse box or under that tape you pointed at.
It used to be common to see dual 87 relays used on a pair of spot lights or dual horns, makes it easy to have one heavy feed wire to pin 30 and 2 smaller wires to each load, one wire off each 87 terminal. Also, aside from the common changeover 5 pin style 30-87/87a, you can also get 30-87/87b. The latter is essentially The same as a 30-87/87 but instead of the 87/87 being always connected together, 87/87b types are independent of each other until the relay is turned on, which then connects both together with pin 30. Something that can really catch some people out is there are 2 different standards for 5 pin changeover relays with 87/87a output terminals. Type A and Type B look identical, until you read the pin designations, where pin 30 and pin 86 are swapped. This can screw you up in a few ways if you install the wrong relay where it needs the other type. Either, the coil 86 terminal becomes hot at all times when it shouldn't be, or 30 terminal only becomes hot when the relay is triggered etc, but the gauge/thickness of wiring for pin 30 and pin 86 is often very different from on another. A worse case scenario of mixing the two types up is when someone swaps the 85 + 86 terminals thinking it will make no difference and all of a sudden the coil ground wire gets connected to either the trigger positive or constant power which should've been feeding pin 30. Even worse, is how Ford here in Australia many years ago used the oddball 86/30 pin swapped type B relays but in a 4 pin style. They wired the 30 and 87 pins the oposite way around, on a switched ground circuit (87 constant ground/30 switched ground) so if you weren't paying attention and fitted the now more common type A relay, you would end up frying your 86 +coil wire by it becoming connected directly to ground as soon as the relay was triggered😁
The relay provides isolation of the 2 circuits fed, and prevents a backfeed somewhere when ignition is off, either through the brain or sensor to another. Probably the last thing added when the test vehicle gave the manufacture the same headache.
My bet is a prior repair couldn't find the DPST (NO) relay that was used, so they wired the two poles together downstream of the relay and used a standard relay. To make it work in key off position, they snipped off the 87A terminal leg on the generic relay (SPDT). Then the generic relay became a SPST (NO) relay but the wiring change made it effectively a DPST. Only issue with this is the contacts might be overloaded now as the OEM surely designed with a DPST to split the load across two contacts for reliability. OEM wouldn't incur expense of a special relay if it wasn't needed.
Given that the 2 circuits have been spliced together, and given that 87 and 87a both feed both circuits, both contacts will share the load so neither contact should be overloaded. The only possible consequence of the 2 circuits being spliced would be a voltage spike from one circuit being allowed to affect the other when the contacts open. It begs the question as to why they originally isolated the 2 circuits.
Very interesting. It is amazing how many folks suddenly have a memory blank and cannot recall anyone fiddling... more likely a family member wanting to make themselves look good in front of family..... You are so right, just because something looks the same. Does not mean it is. Be very careful folks!! in this case it did not matter. But, you do that to some circuits and it will matter and you could potentially cause massive amounts of damage, requiring costly repairs (some even have step down on the output so the output voltage is different for both outputs). As to your printer. There is a couple of suggestions I would recommend it would depend on how much printing you actually do. If your doing a lot or a little of color printing then I would recommend a laser color printer. If not too much then an ink jet printer would be fine but get one with independant color tanks (how many times have you had to throw away the cartridge when most of the colors are still half 3/4 full......And those little suckers are expensive!!!). The ink tank printers are great as you simply buy a bottle of the color when that color runs out just top up that color, nice and simple. In regards to a laser the beauty of laser is, it is super fast in printing. The color toner is a powder not an ink therefore will last so much longer. The toners tend to last a long time much more than an ink jet. But as a rule a laser color printer is not as high a quality printing as a ink jet color.... Myself here I have a black laser printer and a color ink jet.. ( I seldom do color printing but quite a bit of mono printing) and with it being a laser it is super fast it will print and have finished in the time it takes the ink jet to just get warmed up. there is pros and cons to both ink and laser... inks break down over time and can clog up the nozzles whereas lasers do not have that issue. Being a powder technically they have an extremely long expirey value on them. Seperating the printing though isa good choice for example if your invoices are printed out in just black then a black (mono) laser is ideal, fast and neat with no run risk of the text. Likewise if invoices are printed out in color a color laser is good for same reasons. Cost wise... colors are pretty similar in price between them both. The big thing to check with lasers is toner capacity.... my one for example are 8000 pages but some are 5000, 2000 or even 1000 pages....if looking at lasers just find out what your looking at..... Brother and Epson are very good lasers and inkjet printers
A f t e r m a r k e t.... Oddly enough, if Hyundai had tied the two legs together after the relay and before the fuses, a normal relay would work fine in there. I'm assuming they figured the individual loads combined might exceed the capacity of a single leg, so they gave it two!?! Great video, I could see where this would be very confusing! Thanks for sharing this!
The good news is the new relay from Napa showed up the next day and it works perfect. Both sides of the relay (87 & 87) turn on and off at the same time and the car no longer has a draw. Somewhere someone tied those two circuits together though. However, the customer claims the car has not been to anywhere, but the facts are the facts, and we know that is not true. Needless to say, I double checked to make sure each circuit is still fuse protected independently and they are, so I left the whole mess alone. On to the next one!
-Eric O.
Oh damn, spoiler alert, no part 3. I should've read this before posting, but I like to post before my thoughts evaporate, which seems to happen a lot quicker these days. Anyways, you kinda spoiled the thriller ending. BTW, get a laser printer, even a colored one for most of your printing needs and you will end most of your ink issues. Yes, they cost more. Thx for packin us around and givin us the scoop.
Silly when someone bodgresa job to let someone else fix
Good stuff Eric
Flush that toilet and SHIP IT
@@SouthMainAuto sanctum? Damn near wrecked him.
Now it working better than factory....Now both 87 contacts draw each half of the total current, say 2 times 7A (=14A) instead of 1 contact doing 10A and the other one 4A, also totalling 14A. 😂 Less chance that the "10A" contact one burns in. Now, both are sharing the load.😂😂 😉
Looked at the video from 9 months ago and your right that relay back then was white in color not black , love your diagnosis and how you double check yourself and your process , man i wish i had a mechanic like you close by , love this channel
Oh, I didn't see this. I just wrote the same thing. (sort of).
also that taped up wire(s) he mentioned don't appear to be there in the previous video, so something was added or fiddled with maybe.
Same here. Well said.
yep, spotted that as well, relay had a wiring diagram on it so definitely someone has messed with it
*You’re, not your.
Not only is there a different relay in the original video, the wiring harness has the original hyundai wrap instead of the electrical tape shown in this video. And I learned a little bit about relays today.👍
Well that proves the customer is being less then honest, unless someone else has been using and abusing the car and not telling them.
The thumbnail of your original video on this car clearly shows a different relay in that spot. Someone was definitely there after you, looks like they fixed it until it was more broken. I totally understand that feeling when you just gotta know how something is working when it clearly shouldn’t. Great diagnosis, as always 👍
The thumbnail shows the white Hyundai relay as shown in this video on Eric's computer screen. It stands out vividly, and is clearly _not_ the black one seen in this video.
@ yeah, that’s exactly what I said
Super funny before I even read the comments I went back and looked at the other video and saw that it was a shiny white relay not the one that he pulled out
“Once is happenstance. Twice is coincidence. Three times is enemy action.” lol
Crazy to me the owner claims no one else has touched it (see Eric’s pinned comment)
First time to see that 87/87 relay. 80 years and still learning. Thanks!
Same here!
And, the mfgr incorrectly labeled one pin as 87A. They should have both been 87. Shame on them.
Yep, today I learned the importance of paying close attention to the pin numbers of the relays. I could have easily made that same mistake in the past.
87/87 relays are also called a 87b relay. Plenty of them around.
i get confused with red & black.. back in 70,s. id fit relays for spots ect. no prob. now i have to have diag & do slowly, . 67. sik of learning tech sht.. ausie..
There are basically 3 types of relays:
SPST, Single pole single throw, one action, one result. ON, terminals make contact to energize one circuit. OFF, terminals disconnect.
DPDT, Double pole double throw, 2 actions, 2 results. ON, terminals make contact to energize one circuit, OFF, terminals connect to energize one other circuit.
DPST, Double pole single throw, 2 actions, 1 result. ON, terminals make contact to energize 2 circuits from one feed. OFF, terminals disconnect.
Same theory of operation for different switches.
Fantastic find, Eric.
Most techs would have missed this completely and not investigated the relay.
Whoever did that to the relay probably thought they were only connecting the two outputs to tie them together, but they actually made them live in BOTH conditions. they likely didn't check the circuits when the car was KOEO.
The very definition of knowing enough to be dangerous.
Most likely the reason for the DPST relay is because the amperage of the relay can't handle the load on a single pin, so it's split between two pins to share the load. Most relays can only handle a max of 30 amps, and that fusible link is 40A.
Longevity is the reason for the DPST relay, even though a SPST relay will work for a short period of time.
While the two circuits are independent, it's only on the output side of the relay that they are independent. They are fed from the same source, so when the relay is in place they are tied together. When the relay is out, they are independent. Again, it's for amperage rating and longevity.
Looking at the wiring diagram (if you can trust it) the factory engine control relay is a Single Pole Double throw (SPDT) relay with Normally open contacts . When the relay coil is energized the relay closes the two open poles thus allowing power to come from the 40 amp fuse through the switched legs out the 2 separate poles.
_"DPDT, Double pole double throw, 2 actions, 2 results. ON, terminals make contact to energize one circuit, OFF, terminals connect to energize one other circuit."_
This isn't correct, if it has two poles it has two circuits. You are describing a single pole double throw, SPDT. The Hyundai relay is a DPST with one side of the contacts commoned.
I had to go see for myself. It’s pretty cool the act of making a TH-cam video provides the evidence that clearly shows that relay has been changed between that fix 8 months ago and now.
No more wondering 🤷🏼♂️
I would call that relay a normally open double pole single throw relay. Dpst. Awesome video. I am a HVAC tech. I watch your videos because Your electrical diagnostic skills can also be applied to HVAC service. So thanks keep up the good work.
Someone did a whole bunch of extra work to avoid replacing the relay with the correct one. Maybe they were in a pinch and couldn't get one? I bet that story would be an interesting one to hear.
Thanks for the video!
Eric, you had me cracking up so much with your comment, " somebody had there beaters in here" Your one in a million, thanks for all your hard work. Take care
Thanks for the follow-up in the comments! I was afraid I would never know the ending. Thanks for yet another fun ride.
I never thought i would see a Volvo at SMA. Warms my heart. Greatings from Sweden 😊
I have an '07 V70R and an '09 S60. We love them.
What are you even going on about? It’s a Hyundai. Not a Volvo lmao
@@stevemccauley5734there is a Volvo XC70 on the lift next to the Hyundai you donut.
Why are Volvos such crap in the Snow.
@@TheWhale45 they aren’t. People use the wrong tires. A RWD car with snow tires can do fine and a AWD Volvo with summer tires or bald tires won’t.
How is Eric not over 1 million subs yet? Tell your friends. Let’s get him his gold TH-cam plaque!
I had this conversation with my students about a relay with two 87 pins. They are also used in some am light circuits use this type of relay. Power in 30 and out to both lights. Great video
It is my first time running across one. I have likely encountered them just never seen an issue with them.
Run into this with some of the European manufactured equipment I have the "privilege" of working on time to time.. Screws even the most "schooled" of been to this or that education system DIAG Eelekchiken..
Hamm, Dynapac, and Bomag roller/compactors are really fun to deal with, especially with the 24v systems.
shouldnt a split relay, have different draws, hence 2 curcuits..???. seems a cheap way of elliminating a relay. plus, if one powers 2, curcuits, & blows a fuse, then you have more sht to go thru.. dmb ausie here..
always a pain to try to figure out someone else's screw up. good job at thinking it out.
Scotty Kilmer says "you're stupid if you stick a Dodge relay in your car" (while waving his hands frantically). 🤣🤣
He's such a clown, can't stand that @$s hat
Other hacks really make our jobs so difficult. Crossed wiring and missing stuff is frustrating! Thanks Eric!
Mrs O has the right attitude, it's broken, so no harm in trying to fix it. They'll try to sell you another new tank either way.
Especially when things are out of warranty, you have even less to lose.
Talk about confusion when someone else has touched the car , good figuring again 👍👍👍👍👍👍👍👍👍
I wonder if it was a manufacturing option where the same base was used for multiple configurations with maybe a link between those two contacts as an option. But then again, the two circuits coming from it would make that a weird thing to do. It does hint at someone bridging them because of an issue they caused by using a changeover relay.
If it's an ecotank printer, a full waste ink reservoir would stop everything working. Depending on the model the new easy-change ones are chipped so it knows it's been changed. On the older models you need to buy a sneaky reset key online.
There are also non-manufacturer-approved ways of cleaning very clogged print heads involving low lint kitchen wipes and glass cleaner. There are videos of that on TH-cam.
What an honor to mingle with the smart people of the internet. Why are you up so early?
We had that printer for many years. Actually surprised it later this long 😂. Vanessa bought another one to replace it. After reading comments I guess we should have went with the colored laser printer. Next time 🤷🏼♂️
@@pepperpepperpepper You mean "why am I up so late...."
@@SouthMainAuto Brother makes a cheap laser printer (black & white) ink jets suck.
Now I read your comments with your accent in mind. Self induced ASMR🤔
So the correct relay is a DPST with common single feed and some one installed a SPDT. Gotta love that! As for the circuits being powered due to the "beaters" splicing, depends on where they made the splice. If they made it before the individual loads fuses - then not really a problem (as long as you note your diagnosis) But if they made the splice junction after the fuse, well now you have a big potential problem. Because now you have a fuse protected circuit at 20 A may now have 40 A serving it, this could end badly down the road. Getting back to comment about service information lacking, I feel your pain Eric,,,, I feel your pain!
Yes, I was going to say the same thing. The OEM relay is not a double throw relay because when relay is off current goes nowhere, there's nothing hooked to that side. It's a double POLE, single throw relay with the unique feature being common feed to the two poles tied upstream at pin 30. Swap that for a standard SPDT and you've got power going to one arm with key off, where 87a connects. As Eric points out, the mystery doesn't end there because of what he found when relay was completely removed. I like the theory that instead of realizing what was happening, another mechanic jury rigged a downstream connection, not understanding that the wrong relay would also cause a parasitic drain. Hopefully he did that upstream of the fuses. That other mechanic might have noticed that the other arm was not powered up with key on, which might have thrown all kinds of diagnostic codes if the car ran at all. Maybe he thought the problem was in the fuse box rather than the simple explanation of wrong relay.
@@spelunkerd Absolutely! My guess is that by fixing the original problem (relay) the wrong relay was installed and the mental connection did not register so the next fix was to meld the 2 circuits together. I have seen something like that many times over the years. As we both noted, lets hope the joined connection is before the individual circuit fuses and not after.
Consider the problem Eric O found - the relay was stuck closed at all times. The original, double pole relay, split the load going through the relay into two poles (both fed from the same main 40a fused supply.) The fact the relay was replaced with a single pole relay (probably rated for 30a,) and the two loads tied together at the output, now put that entire 40a fused load through the now single relay load path. I suspect that's what made the relay fail. I don't suspect the downstream circuits have any loss of protection, just now the relay load path is all forced through one path not rated for it.
@@ablackformula The fact that branches were fused downstream gave the false impression that the relay had failed, but the story is more complex. That incorrect single pole double throw relay when functioning normally offered a pathway through 87a when the key was off, and through 87 when key was on. So, although it looked like the relay was bad, it wasn't bad and it didn't fail. It simply didn't belong where it was being used.
@spelunkerd ahhh true! Thank you for correcting me.
Don't worry Eric, we know you don't load the parts cannon. Even your 'guesses' are more educated than most people's full diag.
Thanks for the video. This has been so informative for me. I have saved every fuse and relay from every car I have donated to the fire department. I have never thought that the relays could look the same but be different. Thanks again for explaining the processes you go through.
Yup they sure can look alike but be very different!
You’d think they wouldn’t make that oddball relay be able to fit in a run of the mill Bosch style relay socket. Good detective work as always, Eric
Wish SMA was a bit closer to my home. I live about 450 miles away but would consider the drive if my vehicle would make the trip when it needs servicing. Every time my wife hears your voice Eric, she always says are you watching your boyfriend again lol. Great work Eric as usual
I'm halfway across the country, and feel the same way. He's the most trusted mechanic in my book. 👍
@@jameskane319 I'm completely across the country, and he's MY boyfriend, so hands off!
I'm thinking that after the last 'mechanic' replaced the original 87-87 relay with the 87-87a, they didn't understand why the circuit on 87a lost power with the key on, so they 'fixed' it by jumpering them together downstream of the relay.
Weird that Hyundai used that 87-87 relay though. All the power still needs to flow through terminal 30, so it's not really increasing the current rating. They must want to isolate the 87 and 87a circuits when the key is off. Maybe there's some backfeed issue?
That'd be my guess...
ANd he or she, probably think they fixed it , because it worked for the time it was in their shop.
Yup that's what I think as well. I replaced the relay but now some sensors don't work any more, screw it just jumper the two together and get it out of here.
I think the bottleneck in the relay isn't the terminals themselves, but the contacts. The contacts can only handle so much current, so this was their way of using 1 relay as functionally 2 relays.
I think that the main issue is the contacts in the relay, making them large enough to carry enough current for two loads would necessitate making them heavier, thereby requiring changes to the mechanical operation of the relay, potentially increasing its size, etc....complexity
Holy crap, I don't think I've ever seen a dual throw 5 pin relay until now. Or like you said, that style of relay might have been used on the vehicle I was working on and I just didn't know. Regardless, this was a terrific video and I learned something as usual. Thank you very much!
I've never seen one either. If it was a late 80's or early 90's Ford Mustang, they decided no relay was needed at all for the headlamp circuit and didn't use a heavier gauge supply wire than any of the others. They had a TSB but no recall. Likely the Chief Engineer who signed off was mechanical not electrical.
It’s my first time running across one of those dual throw relays too.
It's a double _pole_ , single throw relay (with one side of the contacts commoned together). Don't mix your poles and your throws, you might offend a Polish person 😀
Hey Eric, so its really funny as I am watching this video, this was actually a test we had to do in Transit when we get promoted to mechanic or if you come in brand new, in the training school our electrical superintendent or the instructor lol. He actually used this example for a test, so he replaced the relay with a different relay so that the power would stay on the entire time, we had to diagnose why there was battery draw and why it was killing the battery. So we had to go into the electrical system and test and figure out what was going on, and the issue was exactly that a wrong relay which kept power on and when one of our guys pulled the relay he actually went and grabbed another relay of the exact style and we continued to have the issue, and it stumped everyone in the class not understanding what else could be the issue and when I checked the entire wiring diagram I saw exactly that, it should be switched off when the ignition is off and switched on only when the ignition is on, so I checked the relay number against the wiring diagram and bang figured that issue out right away. It was fun to learn these types of things because they not only apply in this situation but also can apply in a real life situation such as your video. It's crazy how many "Mechanics" would mess this up by putting the wrong relay in, so yeah definitely shame on whoever did that. I love your video's thank you so much for them all!
I'm sure I will never see this issue in my remaining lifetime, but it is still very interesting and educational. Thank you.
Like the behind the scenes thought process! Very informative! Especially the internet mathematics! "What did we start out making this video for?" as you're grabbing your test light, absolutely hilarious!
Thank you for showing us an example of a work around that has existed since they started putting the fancy little boxes in our cars❤ Sometimes, all we think about is, there's no place like home, we will deal with it if we ever get there.
Great diagnostic, Eric! My view is that, somewhere along the line, someone replaced the relay but didn't have one with double-throw contacts and tied the two circuits together. This would probably overload that single contact (otherwise, factory wouldn't use a dual contact). Now, with the correct relay, it doesn't make any diference, as curent can go through two contacts again.
Things like this make my head explode, good thing there's guys like you that can think through it and make sense of it so guys like me can relax knowing Eric's got this.
Eric, you are remarkable. Finding a problem after someone else installs the wrong relay is as good as it gets.
Just worked on a Hyundai Genesis Equus earlier today. Instrument Cluster was completely black. She thought she needed a new one and ordered it for me to install. Fortunately it was an easy fix I just reset the memory 30 amp fuse. Cheers 🍺
This guy has the best job security. He's straightup flirting with the HR lady!
I guess my concern would be if the wires are tied together after the fuse, you might have a wire that's only rated for 15a tied to a 20a fused circuit . Witch could be a fire hazard. Awesome diag as usual!
EXCACTLY WHAT I SAID, & I KNOW SHT.. ausie.. dpst relay, seems a way to have 1 relay do 2 jobs, but then, your fuses blow & twice the pain to konw whats wrong..where..
Great video as always, I don't think I've ever seen a relay like that!
Okay, If that relay is powering both circuits, then you should be able to control those circuits with a 4 pin relay as long as the power, ground, and control pins match the fuse box wiring. I believe that the pins on that 5 pin relay do not have the same configuration as the original factory one. I had problems similar to what you are finding on some of the BMW's I used to work on. Great diagnostic work. Thanks.
When I started off at my first dirt assignment after a year in school one of the sergeants came up and handed me the largest flat bladed screwdriver and said this is a “one level” you can work on anything it fits. As time went on you were allowed smaller tools to utilize working up to a “seven level” in the field which was a plastic tuning wand with the metal inserts. In electronics you could do the most good or bad with the smallest of tools. Component level diagnostics were required.
Mr. O hands out the tuning wands…
Good find. I know it’s not correct, but you could have fitted a standard 4 pin relay just to test if circuits were tied together. Thanks once again for sharing your day and keep up the great videos. 👍
Very valuable video. About half the population purchases used cars. These vehicles are being sold for a reason. Something exactly like this may be one reason.
You should definitely get a color laser printer. No going back afterwards, fast and reliable. Reasonably priced nowadays too, I recommend something like a Brother HL-3220CDW
also, quite the gaming rig for Mrs. O!
Agreed, stay away from HP and look into refillable toner or at least a model that accepts third party toners.
Second Brother color lasers. Have a 13 yr old MFC-9330CDW, never had an issue, will accept 3rd party toner if needed.
+1 more. Inkjet is junk, especially the "razor blade" philosophy of buying the proprietary cartridges.
Bought a laser printer, best thing ever to do
, inkjet are ok, but never last and always plug when not used often or cleaned
Can confirm, ditch the ink jet printer, waste of money. Go try a black and white or color Brother laser printer.
Nothing better than an ice cream and a new episode of SMA
for temporary test, put a jumper from "87 to 87a" then insert 4 pin relay (or use fancy external jump tester) to do the same thing.
but very probably smoked wire harness and shorting out underneath the fuse box/elsewhere also.
I was on the edge of my seat for the entire video with my head spinning. Most impressive on your thought process and diagnostics, as usual. Good work. Electrical issues for the most part are not my favorite repair jobs. I don't have the equipment as you do or the extreme knowledge. Perhaps in my next life I will be an electrical engineer!!!! 🦉
I understand less than half of it, and still find the analysis fascinating. Often he explains it so well that I do get it, as a complete armchair mechanic. It's like watching Big Clive explain electronics. He's in the comments, by the way.
Very good find Eric O! Proved you can't always just stick a like looking relay in place of another just because they are the same size and have the same number of 5 terminals. Must go by part numbers when comparing like size and looking relays. That is why they have part numbers on them and the spades are numbered.
Somebody set this trap up for failure and you were smart enough to catch it. Thank goodness for wiring diagrams or you would have never knew about the double 87 relay.
Wow this tales me back. About 15 years ago i got caught out with a double 87 relay on a piece of machinery. Great spot Eric.
My service truck uses 3 relays to cancel the PTO from being switched on depending on if the air brakes are set, the rpm’s are at idle etc. I was looking at them as my PTO wouldn’t turn on and two of them are tan and one is purple, the Orielly’s cross refrence for them is the same but the purple one is normally closed while the tan ones are normally open. It ended up being the air brake switch but I can see someone not paying attention and putting an Orielly’s relay in there that’s wired backwards and the pto wouldn’t ever work. Great video, never assume you’ve seen it all.
I see someone has had there fingers in there messing with things.
There are many types of relays about so make sure that you change the same one that is already fitted .providing that someone has not fitted the wrong one to start with ..
This does not follow the wiring diagrams so you do need to check it out for yourself so you know what the problem is.
Make sure you let the customer know to cover yourself 👍👍👍
I work in he medical field and I love to work and figure things out like you, do in these videos. You would/could have made an excellent physician.
Awesome. Love stuff like this. I just fixed a car with 78 miles on it, missing fuse for the wipers and the same rating spare was also missing. There is a place where all the automotive gremlin answers live, but we'll never find it.
Thanks for taking us along with you ❤
The relay that was in there was a Single Pole Single Throw (SPST) relay. The "87" is the normally open contact and the "87a" is the normally closed contact. When the relay is not activated, the circuit is connected to "87a" and when activated, it switches to the "87" terminal.
The "87" "87b" is a Dual Make SPST with two normally open terminals 87 and 87b. The Dual make SPST relays are used to power two circuits at the same time that are normally isolated from each other as shown in the diagrams. Either relay will fit but only one will work properly.
Great video! Even Mrs. O was caught "pulling wrenches" in the kitchen. Once in a while you get a job that feels like running in quicksand.
We need part two!
Well done once again. I especially liked the "If I can do it..." part. "Well, some of you can..." ;) I know those little relays have been the cause of a LOT of incorrect assumptions when Shadetree Inc. starts easter-egging relays.
Eric. Relay contacts have a make and break current rating. Sometimes engineers will split the circuit between the two contacts to stay within the contact ratings. This is also important if any of the loads have capacitors or incandescent light bulbs which cause a large current spike when the contacts close. The current switched can also reduce the life of the contacts. Depending on the loads, it can be a good idea to split the load circuit becase you cannot always count on the dual contact poles closing at exactly the same time (within milliseconds of each other) where all the funny stuff happens. One contact could take all of the load for a split second degrading its life. There is also contact bounce but that is a little deeper consideration. Great Video
What they did would have worked if they had used a four pin relay, there would have been no fifth pin to keep the other sensor circuit live so no current draw. There must be a reason why Hyundai use a double pole relay in the first place so I guess sooner or later something would have failed!! Glad you got there in the end, as half way through I was shouting at you Eric, It SHOULDN'T WORK I even paused the video to look at comments to see if anyone else had spotted it, then watched the rest and then you tumbled it. Thanks for a great video!! but then I enjoy all of your postings I take away something from every one.
Who changed that relay? I don't know! (Says the 7 year old, it wasn't me!) Good job as always!
Excellent follow through. Thank you. Pays to know what you are doing. Often times, Divine inspiration. Thank You Jesus
So, the previous repair by someone else was "install whatever relay you have and change wiring to match it"?
Great video!
Excellent work. Not just a top diagnosis, but then to think "hang on a darn minute. I fixed it, but it should have been more broken before" and query that. I doubt many of us would have thought any more about it once fixed. But we really need a follow up. How'd Mrs O get on with that printer? If she got that thing going again she might need to put up a video herself. She could title it "After the other guy spent hours fiddling about, here's the real fix". 😉
Your too humble. That was far from elementary. I am amazed by your aptitude.
The relay bit was new to me... a current draw, not caused by a faulty component but for a relay 'hang-up'. Could be useful as I do most repairs myself. Thank you.. Could possibly save me some money! 😎👍
Good find. In a pinch you could just break off the 87a until the new one arrives.
Nice job Echlin!!! Great customer service. Thx Mr O. My local NAPA is Van Wickle and they are a MAGNIFICENT example of this.
Trowing in a standard 40a 4 pin relay in place of the 5 pin would have fixed this car...at least for awhile. However, since we don't know what the total current is of the 2 combined circuits, it may be overloaded. The manufacture put that double pole relay in there for a reason.
I love these videos where Eric seemingly gets everything figured out and it looks like the video is about to end, Then something goes off in his head, and he starts thinking out loud because something doesn't make sense. Now we get another 20 minutes of video.
Great troubleshooting story, thanks for bringing us along!
Nice job Eric. I love how you verify your work and make sure its all 100% correct! I recognized that Hyundai by that gcustom Napa ground cable you installed on the shock tower right by the fuse box. Yeah someone was definitely meddling around in that electrical system clearly evident by the hack tape job on the wires in front of fuse box. Ink jet prinnters are s pia, maybe its time for a lazer printer - its a business expense, treat yourself & Mrs O!
Great video as always! Went back and rewatched your video from 8 months ago. Somebody definitely swapped relays after you worked it. Love the troubleshooting vids!
Big fan of how your test light uses those jaws. I'm going to be modifying mine.
I was busy typing a comment asking how the hell that car runs and then you started to mention it in the video 😂😂. Hyundai really like weird relays just like the white mini relays which are just jumpers.... who remembers that video ? Awesome and entertaining video as always...................SWEET GAMING RIG BY THE WAY
Amazing diagnosis. I work on my own vehicles and only have my own brain to figure out what I may have previously done.... don't have the issues of what someone else did. You, on the other hand, need Sherlock in your head when you open the hood. I would have never found that incorrect relay. Especially since it looked at least in color and appearance like its neighbor. Nice Job!
The reason for the two circuits is the current rating on the contacts - you want the contacts ratings to be higher than the fused legs off each. They also saved the cost of an extra relay and created a planned obsolescence checkpoint for owners.
Love it, I've only seen something similar years ago with a Mazda 3 that had a bizarre draw that shouldn't have been there from what I gathered was a stuck relay. Replaced the relay with a factory one and the draw was gone but it was a 5 pin and the harness had been touched by another shop much like yours. Never went to in depth with it as the draw was fixed but now you've got me thinking 🤔
Yeah, like one of your viewers commented, it's a double pole, single throw. But you understood it's operation.
This channel never fails to A: teach me something new (Eric is my Jedi Master though he doesn’t know it); B: make my brain connect on all cylinders; C: help me forget about life for the length of the video. It’s crucial to my and many others existence. You just need to accept this Eric and give yourself a pat on the back.
Would love to see more "off on tangents" videos. I thought I was going crazy and my wife was giving me odd looks when I was talking to the TV.. "how wasn't there any codes?", "how did this thing even start?", "why do I not understand what's going on??".
Retired from the automotive scene in 2019. Never underestimate an idiot with some electrical tape and a knife. Some of my best horror stories on cars have been a result of their meddling. Some of my best horror stories have been the result of trying to undo what some backwood in reds have done. Always remember we have to have these idiots in the world because where would we get our stories from and who would be talking about
Different relays can have wildly different internal current carrying specs, too. Since original was driving two separate loads, internally it may have a higher current rating than the Mopar one. But spec sheets would bring that to light if they could be found. There must be a reason to keep the two loads on separate wires also, just tying them together and using the Mopar part could very well cause the one leg to get too hot. You are right to get the correct part and (in my opinion) you should disconnect the two wires again primarily to prevent future possible confusion but obviously that's time.
That tangent was important. It helped show the DX'ing process when someone has modified the harness.
Hi. The outputs from the relay probably got joined to get the engine to run with the remote start system. If you pull the fuse from one side of the relay output it will still have power on both sides. Cheers MD
I've been watching Eric's videos for years, but i am not a mechanic or have any training on fixing cars. I enjoy watching him troubleshoot and determine root cause. He's funny too. What i dont understand is why wouldn't the owner tell Eric that work was done on it since it was last at his shop? Overall, why aren't people honest about that stuff? I struggle to understand why people would withhold that info. What's the harm to the customer? They must know that info would be helpful to Eric, no? I can imagine this is incredibly frustrating to mechanics.
That's a new one. A lower amperage split (87 - 87) relay and 2 independent circuits on the relay load side.
If all the load side was on one side of the relay, that would require a special and more costly relay. This way you can use a relay already designed and in production already at a cheaper cost just by adding two wires to the circuit which is cheaper than that special relay......PLUS the 2 pole 87 - 87 can be used as a light weight diagnostic tester already in system due to the 2 pole output for the 2 circuits, if one had a problem.
Ya, I know, "That's a stretch!"
Anyway, hope the new relay solves the problem. No known reason the old relay was removed, other than shot gun diagnostics?
Good one Mr. O. Nice to see Mrs. O again. Where's your cat?
This time of year with the super cold here in upstate NY, Iv'e run across many battery/alternator changed by others with the same battery goes dead issue.However, you discover the customer only drives 3 miles to work and back. Not enough recharge time for that cold battery. I have fixed many by just giving that poor battery a pep up charge.
A couple of points from an electronics perspective:
1. The reason the 87-87 style of relay is used is so that the current is split between the relay contacts. The terminals are probably rated at 40 A, but the actual contacts will have a lower rating.
2. The disadvantage of the current (hacked) configuration is, if you get a short, it'll blow all three fuses, not just the one on the circuit that's faulty. This isn't a safety issue, it'll just make it slightly more difficult to diagnose.
I think you nailed it. Too much load on one set of contacts. Probably why the other 87a relay failed and welded its contact together. Wouldn't doubt this comes back in the future.
Why don't they design two independant relay's ?? Less confusing, less everything, standard parts, yes, one-more-part, and the space and wiring for one more relay,... but I see more negatives than positivs,....
@Discretesignals It did not weld itself together. It was on the dead pin in the powered off state. But because of wherever they put the jumper, it powered the circuits from the other pin that would be hot in the deenergized state.
A quick test to show the circuits had been joined would be to pull all 3 'sensor' fuses and then see if the two 87 contacts in the relay socket were shorted - the oem diagram says they should not be. My bet would be a link either on the back of the fuse box or under that tape you pointed at.
It used to be common to see dual 87 relays used on a pair of spot lights or dual horns, makes it easy to have one heavy feed wire to pin 30 and 2 smaller wires to each load, one wire off each 87 terminal.
Also, aside from the common changeover 5 pin style 30-87/87a, you can also get 30-87/87b.
The latter is essentially The same as a 30-87/87 but instead of the 87/87 being always connected together, 87/87b types are independent of each other until the relay is turned on, which then connects both together with pin 30.
Something that can really catch some people out is there are 2 different standards for 5 pin changeover relays with 87/87a output terminals.
Type A and Type B look identical, until you read the pin designations, where pin 30 and pin 86 are swapped.
This can screw you up in a few ways if you install the wrong relay where it needs the other type.
Either, the coil 86 terminal becomes hot at all times when it shouldn't be, or 30 terminal only becomes hot when the relay is triggered etc, but the gauge/thickness of wiring for pin 30 and pin 86 is often very different from on another.
A worse case scenario of mixing the two types up is when someone swaps the 85 + 86 terminals thinking it will make no difference and all of a sudden the coil ground wire gets connected to either the trigger positive or constant power which should've been feeding pin 30.
Even worse, is how Ford here in Australia many years ago used the oddball 86/30 pin swapped type B relays but in a 4 pin style.
They wired the 30 and 87 pins the oposite way around, on a switched ground circuit (87 constant ground/30 switched ground) so if you weren't paying attention and fitted the now more common type A relay, you would end up frying your 86 +coil wire by it becoming connected directly to ground as soon as the relay was triggered😁
Seems like a good example of when CYA pays off. Good notes never hurt. 🙈
Some vehicle owners are economical with the truth.
That relay must have changed itself!
Another great video Eric 👍
Love the ASUS ROG in the corner Mr. O. Who would've thought you knew more than just cars. 😛
The relay provides isolation of the 2 circuits fed, and prevents a backfeed somewhere when ignition is off, either through the brain or sensor to another. Probably the last thing added when the test vehicle gave the manufacture the same headache.
My bet is a prior repair couldn't find the DPST (NO) relay that was used, so they wired the two poles together downstream of the relay and used a standard relay. To make it work in key off position, they snipped off the 87A terminal leg on the generic relay (SPDT). Then the generic relay became a SPST (NO) relay but the wiring change made it effectively a DPST. Only issue with this is the contacts might be overloaded now as the OEM surely designed with a DPST to split the load across two contacts for reliability. OEM wouldn't incur expense of a special relay if it wasn't needed.
Given that the 2 circuits have been spliced together, and given that 87 and 87a both feed both circuits, both contacts will share the load so neither contact should be overloaded. The only possible consequence of the 2 circuits being spliced would be a voltage spike from one circuit being allowed to affect the other when the contacts open. It begs the question as to why they originally isolated the 2 circuits.
Your ground wire still looks perfect from the former repair
You get paid for the years, not the hours. Nice find, Sherlock! ❤
Very interesting. It is amazing how many folks suddenly have a memory blank and cannot recall anyone fiddling... more likely a family member wanting to make themselves look good in front of family..... You are so right, just because something looks the same. Does not mean it is. Be very careful folks!! in this case it did not matter. But, you do that to some circuits and it will matter and you could potentially cause massive amounts of damage, requiring costly repairs (some even have step down on the output so the output voltage is different for both outputs). As to your printer. There is a couple of suggestions I would recommend it would depend on how much printing you actually do. If your doing a lot or a little of color printing then I would recommend a laser color printer. If not too much then an ink jet printer would be fine but get one with independant color tanks (how many times have you had to throw away the cartridge when most of the colors are still half 3/4 full......And those little suckers are expensive!!!). The ink tank printers are great as you simply buy a bottle of the color when that color runs out just top up that color, nice and simple. In regards to a laser the beauty of laser is, it is super fast in printing. The color toner is a powder not an ink therefore will last so much longer. The toners tend to last a long time much more than an ink jet. But as a rule a laser color printer is not as high a quality printing as a ink jet color.... Myself here I have a black laser printer and a color ink jet.. ( I seldom do color printing but quite a bit of mono printing) and with it being a laser it is super fast it will print and have finished in the time it takes the ink jet to just get warmed up. there is pros and cons to both ink and laser... inks break down over time and can clog up the nozzles whereas lasers do not have that issue. Being a powder technically they have an extremely long expirey value on them. Seperating the printing though isa good choice for example if your invoices are printed out in just black then a black (mono) laser is ideal, fast and neat with no run risk of the text. Likewise if invoices are printed out in color a color laser is good for same reasons. Cost wise... colors are pretty similar in price between them both. The big thing to check with lasers is toner capacity.... my one for example are 8000 pages but some are 5000, 2000 or even 1000 pages....if looking at lasers just find out what your looking at..... Brother and Epson are very good lasers and inkjet printers
A f t e r m a r k e t.... Oddly enough, if Hyundai had tied the two legs together after the relay and before the fuses, a normal relay would work fine in there. I'm assuming they figured the individual loads combined might exceed the capacity of a single leg, so they gave it two!?! Great video, I could see where this would be very confusing! Thanks for sharing this!
I wonder whether someone tied those legs together, thinking they could use that relay. Weird..
This was interesting. Thanks!