How to Not Fry Your PCM- SBQM Channel Free Video Sample!
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- เผยแพร่เมื่อ 5 ต.ค. 2024
- This is a sample video from my other channel Schrodinger's Box Quantum Mechanics. The channel is here:
www.schrodingersboxqm.com
This video is the final part in a 4-part series I did on techniques you need to master if you plan to do the PCM controlled component testing you often see me doing without frying the PCM.
If you would like to master this material and be more confident in your PCM electrical testing skills, head over to SBQM and you can finish watching the entire series for free within 2 weeks!
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We have no excuse not to step up our diagnostic abilities with this kind of (free) content 😎
This guy is absolutely brilliant. No wonder he's so popular. You wouldn't get this level of tuition at college, let alone on any other TH-cam channel. And this is one of his earlier videos - he's only gotten better since!
🙏🏼
Yes. He is incredible.
Been doing air-conditioning and refrigeration for 40 years and now I'm retired and I enjoy working on ars and just learning automobiles and diagnostic but I have always used the troubleshooting any electrical problem source ,path switch , load and sequence of operation to test electrical circuits and don't get overwhelmed with the electrical diagram or schematic ,just knowing what isn't working and only be concerned with that find the component and follow the path backwards to the voltage source .I have enjoyed your videos and I have learned in a few weeks of watching you and your explanation of the sensors and components the ecm and the pcm are controlling and that's what I am looking for thanks for sharing your knowledge and I am going to subscribe to your advanced learning channel. Looking forward to learning
and sharing some of my experiences and helping younger students and future technicians
30 minutes extremely well expended.
and I passed all the tests,.
thanks to you of course.
Gotta love the negative commentors who wouldn't know how to diagnose a dead battery much less a TPS. Am I wrong or would only a fool thumbs down the source of knowledge that would finally make them competent?
I don't think a smart knot with a balljoint hammer would make them competent-- they know how to cross thread spark plugs. Most of us like to know how to diagnose and (repair). People like to hate what they don't know or understand. Your channel is extremely informative, thanks for taking your time to teach us!
Jeremiah johnson "People hate on what they don't know or understand"
Words of wisdom there my friend- that is so true!!!
+Schrodingers Box I don't think the test done around the 14 minute mark is a good one because if the coil was shorted then you could draw more than 10 amps and blow the meter fuse, your thoughts?
+Nikolay Baranyuk Good point- you're right!
bidoubleo tiwhy Happy thanksgiving to you too my friend.
And yes- the comments are gold on this channel. I also learned more from the comments than I have in 7 years of doing this hobby- by far!!
Thank you for the fuel trim diagnostic information. Really helped me understand something I knew nothing about. This guys a genius
Also very important have the the right size terminal to probe the terminal to not overspread it. And to test the drag on the terminal for a good tight contact. In my 30 years experience many problems are caused by other techs spreading the terminals causing additional problems .
In your 30 years experience you use a noid light set instead of just a test light???
Just love this topic, it shows that you've to know and be patient when coming to electronic wire harness and their sensors and modules. Thank you Matt. Great work 😀👍🏽👏🏽
Your explanations goes down soo well. It's very easy to understand you than most of the videos i do watch. Thanks keep it up.
Glad you like them!
Thanks for the knowledge, it has improved me tremendously in the diagnostic side. Your a very good teacher.
Great video,your right about doing this stuff on cars,you can look at diagrams all day long but nothing beats the testing experience.
Great video Matt. At 19:36 you mention that it would be a good idea to use a fused jumper wire which I agree with because there is a small possibility that the underlying problem was an internal short in the injector. That in turn would blow the fuse on the wire supplying it with power thus matching the previous symptom of 0 V coming to the injector. But if we then supply the injector directly the jumper wire might carry enough amperage to blow the pcm. So it would be best to always use protection ;)
I'm so happy that you were so nice to people who didn't understand why the paper clip was a bad idea, LOL.
The best teacher I have ever seen thanks for your efforts
You made my day sir. Your info is just what the doc ordered. Thx.
Thanks you made my day too!
Just found you on TH-cam all I can say is simply amazing content also video length is perfect for my treadmill use every morning 👍🏻
Glad you enjoy it!
I have basic electrical knowledge, very basic(even though I'm the son of an electrical engineer :P
). Thanks to your videos, which I sometimes watch several times to understand and make this knowledge and understanding sink in, it is quite easy. Very clear explanations along with illustrations on the white board make it really friendly. Thanks again! I would just add a warning for other beginners who use any wires or test leads to be careful, when, for example, improperly leaving uninsulated wires, they do not accidentally short-circuit those that will cause damage, e.g. fry the PCM or start fire. Sometimes engine vibration/closing doors alone can cause contact and short circuiting. I wish You best and thank You again. We need more people who approach things like You do!
Thanks for the comment and yes- it takes most people several times watching before it sinks in. I am the same way!!!
Brilliant brilliant video. I'm going to be joining your membership. Iv been a membership of mercanic mindset for about a month now .And watching pine hollow auto diagnostic and subscribed to you for a few years now IV learned a lot about the basics on this one.👍
Thank you! I guarantee you won’t be disappointed!!! It will be the best $3.49 you ever spent I guarantee.
Awwwwwsommm! Just what I needed not to fry my ECM- signing up for the subscription!
Thankyou for the info.Reading other comments proves your correct that we all learn our own way to diagnose even when they do not know it and turn to negative remarks. Thanks again.
*Thanks, great video. Like you said in the beginning of the video, if you don't know basic electrical, learn before you start testing. It seams the Auto industry purposely make many sensor's that eventually fail, but what you are saying is that you have to look at the whole picture because it can be different problems. For Example; I just changed my fan resistor and wire connector because my car was overheating. Yes, the resistor and connector wire was burnt, but the radiator was also clogged, and I had to change the radiator, but I had to go much further and change the thermostat and The cheap plastic housing. That finally solved the overheating problem. Thanks!* 😂😂😂
Its amazing to me that anyone who owns a computer can't afford 4.50 a month (about 15 cents a day). Most people probably lose that much in spare change every month. There is nowhere else I could find this quality of information for this price. Keep the videos coming!
+brad wettig I like the math reference!! I easily lose 15 cents a day from my pocket digging my car keys out!
+brad wettig For just 15c a day, you too can help freezing biologist-mechanics in Colorado warm their garages through all 9 months of winter.
John Ris Hahahaha OMG please dont send Sally Struthers over here- I don't nearly have enough food for her
Thanks Matt!
This video was double GOLD!
God Bless!
Yes, please produce a video on Bi Directional Scan tool!
I will be purchasing one in the very near future, and need the tutelage on how to properly use it!
You have my thumbs up and subscription! 😃
Awesome, thank you!!
I'm definitely better at the mechanical than the electrical but this crash course is worth its weight in gold.
This guy at times can be bit of a smart ass but can you imagine the comments he has to read. On the other hand I learn everyday. This guy is great!!!!
Thanks- yes I do bite back in the comments lol!
Thanks for your videos, are much educational and I'm from South Africa
Great stuff. I thank you for sharing your knowledge. I want to understand concepts and using critical thought in my work.
You are in the right place!!! So far i've only found 80,000 others like is in the whole world so we're not too common in this field!!
Looking forward to your videos on diagnostics with scope. I've been using the picoscope for a while. But it actually doesn't matter. Once you get the basics and realize what you're doing you can work with any scope.
This video is a great example for anyone considering joining the SQM community to go for it. This is a final video in a series on the SQM channel. The prior videos teaches you what he is summarizing in this video. Can't recommend the paid channel enough.
Thank you my friend!! Glad you finally got access!!
I am a retired electronics tech . I am no expert mechanic but I have repaired my cars since my 20's (now 82) and have reasonable mechanical skills. I have rebuilt a couple of engines, but there is a lot I can't do and a lot that I don't know. I drive a 1992 Ford F150 that has three relays. But I have been paying attention to the newer cars too, and have helped troubleshoot a couple of them. That taught me how much I don't know. Right now I am working on my grand daughters 2010 Cadillac srx. I had to get a new scanner and it shows a U0100. From the symptoms I believe the problem probably is a bad ecm, but I am checking the power and grounds to make sure it isn't something else. Anyway, bottom line is that I have decided that modern cars are really computer systems with an engine attached. I find the automotive electronics very interesting and want to learn more so here I am.
Application of fundamental understanding, I have learned alot from your videos , desperate to see complete series.
Another great video on electrical diagnosis. It seems some people were really trying to get your goat below. I see you held your own but you do make it too easy. Trolls will be trolls. The issue with the use of a scope is not so much price but the steep learning curve involved in getting useful results. I recently bought a non-automotive Picoscope (2205A) and have been learning to use it for relative compression, secondary ignition wave forms, current ramps, etc. I have spent hours learning how to set up the software (Picoscope 6) and probes(amp clamp, induction, etc).
For some reason you jumped onto my recommended videos and for that I am thankful. New subscriber.
Thanks for subbing
Enjoyed you and descriptions of other Knowalls but know little....Enjoyable series of videos...all the best and keep well. N.Ire. The U.K retired and love the show.
gotta love them ls engines! I just did an ls1 swap in my thirdgen Camaro one of the hardest things iv done wiring wise but I had to learn it all on my own witch made me much better at it, its so cool seeing you do exactly what I did when wiring my car up
Matt, you and your videos are just fantastic man .
Wow, thanks!
A thumbs down does not mean it is bad content. Sometimes it is the way it is delivered.
Yes, there are some people who are too stupid to realize the content is all that matters
Your The BOMB BRO!!!! (Some having a radiater fan not working situation ), I seen people use a paper clip to insert into the coolant temp sensor end that feeds power/signal to the coolant sensor to bypass the sensor to see if fan then works Is this a nono too?
Why unplug an injector when testing them at all when you own a graphing multi meter and a low clamp probe? IMO a test light a scope or graphing meter like a vantage and a low amp probe you can test all PCM circuits completely safely. In my whole life as a mechanic I have never seen a test light ever damage a PCM, ever. I think it is more of an urban myth of mechanics.
+South Main Auto Repair His target audience do not have Vantage Pro nor a low amp probe. Do it yourselfers don't have expensive diagnostic tools or it defeats the purpose of saving money. I do agree with your and Ivan's point of view on scope on a rope.
Well I am just thinking with it being an advanced diagnostic channel and given the price of scopes and graphing meters now days it would only make sense. I just bought a 2 channel USB scope that for less than $100 ya know. There are some really good deals on some good used stuff too.
Please let me know what kind USB scope and how you like it. I've been contemplating an economical way to get a scanner/oscilloscope. A used SnapOn Modis looked promising. However, the update cost, and your experience with your Verus gave me second thoughts. It looks like a AutoEnginuity and PC based oscilloscope is the best way.
+Qiong Jia hi I have the autoenginuity and I would not recommend it unless your a diy'er or don't want to spend more for pro level scanner. I find the PC scan tools like mine are very buggy and just wig out at times. Bi directional , not many functions. Hard decision , just depends on your budget . Hope this helps , just my experience others might have a different opinion .
Steve, what do you recommend? New Maxisys or used Verus/Modis? I understand Autel is being sued by some Manufacturers. It has more features, most are hacked. Since it is a Chinese company.
Brilliant demonstrations, even though some people think you go over the top with the explanations! Of course having the right electric wiring diagram is a must. Any idea where your viewers can download the Ford wiring diagrams, preferably for free?Keep up the good work.
Thank you sir for all you do for us like you said we need some more video basic electronic diagnostics sir
Just awesome and crisp explained. I definitely love your videos man!!!!!
Very good explanation
yes it was a very useful lesson for me thank you so much
YES more on basic electrical please...
Duly noted. My pay channel has LOTS on basic electrical diagnostic procedures. Very step-by-step. Still in process of development but will let you know when it's ready!
FINE MATT.... FINE!
I'll go do my free trial of your new channel. But, somewhere deep down I know this is going to be like taking the free hit from the heroin dealer.
Pretty soon I'm gonna be pawning stolen sneakers for a SBQM fix.
Damn you!
Actually I have just been waiting for a nice long weekend to start the trial. So good job on the timely reminder.
+John Ris Hahahahaha all part of my master plan lol. Big difference between what I'm doing and a drug dealer though- I purposely target schools lol.
+John Ris Not a fair comparison. Heroin just makes you feel good, this stuff allows you to improve your life. If only all knowledge was that addictive. I know that SBQM is going to be a valid monthly expense for me. It will easily pay for itself.
Thank You Scroding Box you have a great VEDIO class room instructions solid advise
Please do make a video on how to use a scan tool. That would be helpful. Thanks
Matt good job. I have something I would like to add. When you were checking battery positive supply at the injector connector unplugged that test is not totally valid. That test is only telling you if you have a open circuit or not, you are reading static voltage. You have to load the circuit to see an actual representation of the voltage at that wire. So hooking up a test lamp or using a substitute load rated the same amperage the injector is would be a better test. Or use a Loadpro which is what I would use.
+busjockey1 I was not testing for voltage drop at that time but I do check voltage drop through amperage measurement later
+Schrodingers Box Alright so you were just checking to see if you had static Voltage? Sorry that just threw me off because you said that was a valid test. For checking for a open circuit yes. I understand your process here but you might want to clarify the difference between a Static Voltage Test and a Loaded Voltage Test: Voltage Drop. Someone new to doing this type of work could get confused and in effect not do these measurements properly.
+busjockey1 Yes remember this video is part of a whole 4 part series where I talk about all this stuff. I also talk about static vs loaded voltages in my video on voltage drop on this channel.
I figured you did it's just at that part in the video on how you did that test I think it would have been a good idea to clarify this difference between the static and Loaded Voltage. Not trying to be a pain at all it's just I want everyone to understand the difference between these two readings. Keep up the good work.
I will check out your premium channel, looks interesting.
Thank you for the information.
Thank you Master for share your knowledge with us, well explained 👍
Outstanding.
Great video. Happy Thanksgiving to you and your family also.
+John B. Kobberstad Thanks John, same to you and your family!
Well done.
Best video 👍🏽😱 great instructors! Great brake downs and examples!
great video , priceless lesson thanks matt .
Makes sense to me, good diagnostics
I really enjoy your videos, Matt. Good job!
Very special stuff, thanks.
Glad you enjoyed it!
Matt
I am going to subscribe to your pay site tomorrow. Loved this video!!!
Thank you!! You will love it I guarantee!!
very educational. thank you.
Hey thanks Loving it big guy
You should say the dVOM in volts mode in more resistance rather than using the word load. When you said it was more load that sounds like more amps and less resistance to me. But then again I am used to higher AC voltage in the HVAC field so maybe it's valid.
*is more resistance
+Joe Shearer True
+Schrodingers Box thanks for the reply. You have a great channel. I'm a 2%er in my field too.
Awesome explanation sir, I found this video related to my recent Honda Element issue. I replaced the TPS sensor and during calibration, I feel possibly I fried my ECM because when I used the volt meter I mistakenly connected the black lead to Battery + and the red lead to the signal wire or 5v wire accidentally or both together, I heard a sparking sound but I thought it can be a relay or fuse noise. Well, when I tried to start the car it was cranking but no start. The fuel pump stopped priming on the ignition key in position. The next day I noticed the immobilizer green key flashing in the inst. cluster along with Check Engine Light and oil pressure. Also, DLC or OBD2 connector showed a linking error earlier that was working perfectly. Because of the check engine light, I am still hopeful ECM is good but in some forums, I saw ECU can still be bad. Kindly guide me in light of your best experience for possible reasons and fix. I checked all the fuses and relays are good along with the power and grounds.
Awesome.
That's great
Thank you for posting this video. It was really helpful.
Hi Matt. very good tips. =)
When you measure this type a measure i recomend use the Multimeter VRMS es more exact because the multimeter VRMS cant measure voltage out 50Hz. But if you have a osciloscope not is necesary.
A big Hello from Spain.
Your videos are excellent and you have one bad ass Pontiac .
No argument here lol! Thanks!!
Thank-U-matt&UR-VEWERS💥💫
Yes the viewers are the ones who make it all possible!!!
Aw, look at my handsome man in the intro!
Thanks Baby! Love You!!
not bad at all! i would of thought putting jumper wires with the plug undone to sig/ground and the power feed from battery straight to the 12v pin, bit more mucking around though
A typical ammeter is internally fused at 10 Amps at the 10 Amp setting. Since the power source is fused at 20 Amps, the 10 Amp internal ammeter fuse would be safe for the system -- the meter's internal fuse would be the most vulnerable component.
That is not correct!!!!
Most PCM circuits operate on well under 1Amp. You absolutely don't want to use the ammeter for that reason on such circuits. Use a LED testlight which is 50mA load. Do not use the ammeter!
@@SchrodingersBox I see that I was not specific on which part of the video I was commenting on which led to some misunderstanding. I was referring to the MAF sensor portion of the video which was at about 28 minutes into the video where the 12 Volts was injected through the ammeter into the MAF sensor connector at the pink wire (the pink wire source was fused at 20A and typical ammeters are fused at 10A). This was not referring to the fuel injector and its connection to the PCM module portion at the beginning of the video. For the fuel injector portion of the video, an oscilloscope would be ideal for monitoring the voltage pulses at the switched ground (PCM) side of the fuel injector. I am not sure of how static sensitive these PCMs are but it might be a good idea to be grounded to avoid unwanted ESD (electrostatic discharge) while working with the PCM. Usually, being in contact with the chassis of the car is enough to discharge any damaging static. I would hope that the PCM modules are adequately externally and internally protected from ESD by design -- they probably are.
ah much clearer. yes in that case an ammeter is fine. I normally use an Amp clamp
fantastic
Thank you so much 😀
Great job, well done
i watch youtube because its free.
+mason jack No problem with that!
And $4.99 is very much worth an intelligent group of videos by a good instructor .
Great show!
thank you for awesome explanation
This video is not new and my thoughts might have been addressed, but anyway:
- Let's say the injector is faulty, but we had luck and it blew the fuse before frying PCM. Assuming that, wouldn't it be the safest to unplug the injector, check its resistance (to make sure it's not internaly shorted) and then continue with tests? Because if we just apply 12V to it, we would fry the PCM, as internally shorted injector presents no load.
- On the MAF connector, the viewer assumed the pink wire is power and had an idea of applying 12V directly to it. But if he was wrong, he could have applied 12V directly to the signal wire, and that could be bad?
- Also, let's say that the connector has melted inside, cutting the power wire, but shorting power and signal sockets. If we apply 12V to the power socket, we send again that voltage directly to the PCM via signal wire. Not sure how to test this one, how does DVOM work in a resistance/continuity check? Is it a load in the circuit or not?
Putting the probability of these scenarios aside, I am happy to be corrected if my logic does not stand.
all sound rational to me.
Another great video. Your a great technician an I did scream a few times.
I have to admit I am struggling. Thanks for your help.
That first example! XD
Top notch video. Very well done. Use of the word "load" a bit miss leading - I think use of the phrase "high resistance" fits better.. Thanks!
+B crinshaw Resistance is indeed the load when there is nothing else in the circuit restricting flow to do work.
+Schrodingers Box - Right you are, it surely is a load - as a straight wire across an injector plug is a very, very good load - good enough to fry a PCM like you illustrate. Modern DVM's are a light enough load to keep drivers in the PCM safe. Very good videos! I'm a new subscriber and really appreciate your work. Thanks.
Excellent
U said u get 9v because d injector is on ,how could it b when d hernace is disconnect an your dvom lead is on d hernace
I saw a few videos on MAF sensors and I understood that ECM is sending 5v to the sensor and now I learn that 12v is coming from a battery. I didn`t get the last one.
I saw your video now on maf sensor. It's clear now 5v is a reference wire and maf has a 12v supply wire. 👍
For the last test, a moderate quality DMM (not the $5 harbor freight) will have a 10A fuse for the amperage scale, although they are much more expensive and hard to find than an automotive blade fuse. He really only needs a fused jumper if he is using a clamp ammeter.
You do do some brilliant videos.
Could you do one on why I do not get a battery dashboard light when my ignition is turned on. The alternator is charging the battery at 14 volts.? Any ideas?
There is a wire from the alternator to the dashboard- either its disconnected from the alternator, its broken on the way to the dashboard, its disconnected at the dashboard or there is a failure on the IP circuit board.
what a great youtuber you are sir thank you and take a bow lol
Test lights can be evil to a newbie and when you don't have a schematic and are just probing, use a DVM. It is the safer bet. The test light will always have a lower resistance, aka the bulb compared to a multi meter set to volts. The bulb in a test light can be as low as a few hundred ohms. Ive seen too many people use test lights incorrectly activating circuits or cooking components when hooked up incorrectly. I would use a DVM till you understand how an electrical system works on automobiles. My 2 cents.
Agreed 100%
Hi,
a few comments regarding the injector tests...
assuming the fuse is correct, it should be rated to protect the pcm against a shorted injector solenoid, so the first 2 tests shouldn't fry the pcm (I'm not saying that you should do them, of course, because they don't really prove anything).. The test where you bypass the fuse could be dangerous, on the other hand, in case the injector solenoid is in fact shorted... I really like your material, and actually this is the first time, where I thought - ehhh, that is not completely right... keep up the good work :-)
+hooverphonique I can most definitely, 100% assure you that you you are incorrect and you CAN and WILL fry the PCM by bypassing the injector. I have seen multiple times where a shorted injector has fried a PCM.
+Schrodingers Box so you're saying that the fuse does *not* blow in case you short the injector? why is it there then? just in case the insulation on the harness is compromised?
And if you're so sure it will fry the pcm, I don't understand why you tell people that they can just bypass the fuse to check if something is wrong with the 12V feed..
hooverphonique Correct- on a PCM circuit with no current restriction the driver will fry long, long before the fuse. Remember on 12V Circuits they are virtually always ground side switched, so obviously fuses are irrelevant to protecting the PCM.
I have no idea what you're talking about when you say i recommend to bypass the fuse to check a 12V feed- where did I say that?
Your comment "so obviously fuses are irrelevant to protecting the PCM." is problematic. Fuses are important! The first test to be performed should be to check that the sensor is not internally shorted to ground.
You'll think I'm being a dick, but that's OK. I have to go along with the others, Eddie the Grouch gave the best explanation and definition. Higher resistance = LOWER load. They are pretty much understood to be inverses of each other, and the word Load has a very specific meaning in the worlds of electronics and electrical work._Joe Shearer made the same point equally as well._ We are not trying to be asses here. The word "load" really does have to be used in proper context. _ It implies low resistance, not high resistance, and it implies higher current flow (in relative terms). _With a "low resistance", the current source is will see a relatively "high" load.
+douglas “The flame is dead” lee No I get it. It's explained better in the other parts of the series- remember this is just one part of 4.
wonderful video MATT, But i will thank you if one day you may do us video of how things should be. i mean like this
o2 s1 should be between o-1
o2 s2 should be approximately 0.5v
maf should range between WHAT WHAT TO WHAT WHAT ON NORMAL CAR.
ET CETERA.
BECAUSE I JUST BOUGHT SCAN TOOL , BUT STRUGGLE TO KNOW WHAT SHOUL BE WHAT IF THINGS ARE RIGHT.
BUT AS FOR FUEL TRIMS I EXCEL FROM YOUR BEST VIDEO. HAHAHAHA
KEEP IT UP
M.B.S MOSHITOA(S AFRICA)
Yes what you are looking for is a list of “normal baseline parameters”. It’s something most people try to find when they first get a scantool. Unfortunately they don’t exist. There are so many varibles- ambient temperature, load, engine temperature, RPM, etc that “normal” is always dynamic.
What you do is look for readings inconsistent with conditions AND with other readings. Also failure of a reading to change with conditions is what you look for too. There really is no “fixed baseline”.
There are some generalities though. At idle I expect a TPS of under 7% but again - if it’s a drive by wire system and the engine is warming up it should be around 20% or even higher if engine is really cold.
A MAF at WOT should read a Lb/min value approximately equal to engine displacement.
A rear O2 should not read .5V- it should read .8V at 2200RPM but the most important thing is that it doesn’t duplicate the front O2. But it depends on the catalytic converter temperature.
I love you sir thank you so much
Thanks
Welcome as always!!
Jumper from bat positive to pos on injector….how about a fuse inline on jumper wire ?
+berkmanyt That is a good idea but not necessary for PCM protection since injector is ground side switched.
29:09 Actually, if the ground was broken, you might fry the PCM by passing all the heater resistor current through the signal wire at 12V. It wouldn't be wise to do this before checking the ground first.
+celeron55 Sorry I am not following... How is that possible when the heater circuit is not even connected to the PCM?
+Schrodinger's Box Quantum Mekanix The heater circuit uses the same ground point inside the sensor, which, when left unconnected, simply becomes a path for current towards the measurement side. The ground point will likely reach about 12V compared to the PCM's ground.
It all depends very much on the sensor's internal design though. The sensor may or may not pass a considerable current towards the signal wire in that situation (it's kind of a reverse polarity case) depending on what kind of components the signal output is using. I would be careful because there is no guarantee of what will happen.
+celeron55 Ahhhhhhhh yes you are right! I hadn't thought of that!! I have not been able to see an internal diagram of them sensor but I'll check this out.
Wow fantastic thought- totally never considered that!
+celeron55 The PCM in the diagram shows it to have a pull-up resistor, probably on the order of 1kOhm-10MOhm to +5V and the PCM will have its own similar internal resistance or a MOSFET (from the designs I know) so I wouldn't think that side of the circuit could sink any power to speak of.
Are you concerned that +12V (that you suggested could maybe be linked internally) in and of itself would do damage to an input designed for a +5v reference?
To my thinking, if the ground had failed and the PCM input was of some vulnerable design, the +12V would have already killed the input long before you got there.
+anyheck That's very true! The damage would have already been done if the ground was broken and the sensor-PCM combination was vulnerable to it. So my point kind of ends up being just a curiosity and not very practical.
The viewers diagram of forcing 12v through the pink wire found the problem on the other side through process of elimination. Conversely on the OTHER side of the circuit a corroded 20 amp fuse might have been a problem where the pink wire wasn't seeing a full 12v yet the fuse wouldn't b blown. As a semi-mechanic am I right Matt?
I have never seen a corroded fuse however you would certainly see a voltage drop AFTER the resistance in a circuit for sure.
thx 4 commenting... quick question-- might one accurately test a bad circuit through a fuse with amps? One problem however would b what the correct setting from a computer, say ECM, might b on say a 10 or 20 amp fuse... Worth it?
Cuz me--PCM...
Thanks for your wonderful videos
I would like to ask you as a beginner in which order we should see your videos
As a beginner you should probably join my pay channel www.schrodingersboxqm.com
DVOM in 10A mode has internal fuse protection so additional fuse not needed unless circuit normally has lower rated fuse protection
This is extremely dangerous thinking. Most PCM components are well under an AMP. In fact even under 250 mAMP. A 10 Amp fuse is exactly how you would damage a computer. Measuring amperage with a 10A multimeter is a terrible idea!!!
Schrodingers Box perhaps a misunderstanding or I explained incorrectly. An example.
I want to provide power to +12V side of ground side switching injector so I use DVOM in 10A mode from B+ to injector + pin. Ground side jumped to pcm tor injection trigger. Fuse in 10A mode is for circuit protection not power limitation. Preferable to a straight wire jumper
Still very, very ill advised. Instead the correct method is to use a testlight- incandescent for 250mA, LED for 10mA.
It makes no difference whether you use the multimeter or a straight wire in the application you describe- 10A is not going to protect ANY computer circuit.
Schrodingers Box now I’m confused because I believed as the injector was the load and thereby provide protection for the pcm as I am only providing power through the 10A fuse to the load it’s no different to fuse box power supply except I have a DVOM giving a display to see current flow
An injector is 1 amp AND it is also ground-side-switched as well. Therefore, think about it.... If you bypass the load directly to the PCM with your "10A fused protection" technique, you will absolutely 100% fry the driver guaranteed. See?
ALWAYS use a test light.
I am very very convinced the way you are explain to your followers.and I seeing your video because I have a
Fried he Owen a 2007 seven Hyundai Tucson hare is the problems with this Car every winter
Minas seven it want start.This Man
Went different car garage everyone
Telling him a different story and
Spending 💰 a lot of money to this
Car,.when the weather is warmer it works perfect no problem at all.what
Would be your suggestion, please
Give Us your smart Ideas. I Live in
A terrible weather in Canada Saskatoon, Saskatchewan.
I would start by checking fuel trim. Without that anything is just a guess.
I checked out your new Quantum Mechanics Channel, not for me unfortunately :(
+Brad Halstead The material is not for you or it is not available in your country?
+Schrodingers Box Available in Canada no problem, the material thus far is not for me, not that advanced lol Thank you for the free trial though.
+Brad Halstead Fair enough- I appreciate you at least taking a look! You might try my friend Scannerdanner's Channel- he covers stuff that's pretty out there!
+Schrodingers Box Thanks, I subscribe to Scanner Danner and Eric The Car Guy and Engineering Explained as well as your free channel which is more than enough for my skill level :)