Other way around... It's to stop outside interference from making it's way to the fuel pump. As they do that to prevent the fuel pump from burning up... Why it's driven by the fuel pump module. And at $350.00 for the pump. Then labor to replace them. Seems cheaper to repair the wire...
Just guessing but since the radio amplifier is in the RR corner there may have been issues with EMF coming from the fuel pump which could explain the need for shielding.
Not only from the fuel pump, but I think primarily from the fuel pump driver, since it uses PWM the signal will be a square wave with a lot of high frequency components. Which is why the wires from the driver to the fuel pump should be as short as possible.
Correct. Shielding is common when electrical noise is a concern. Usually it's used when the wire might pick up noise, but it's also used to prevent the wire from radiating noise.
@T.J. Kong you can't use just a capacitor to filter high frequencies from a PWM signal. What you need is a LC filter to make an average DC voltage from the AC signal. But then you've just created a plain old DC-DC buck converter. Could they do that to filter the noise? Yes, but coils and capacitors cost money, and if you can get away with not using them, they won't. It's debatable whether installing the shielding over the cable harness cost the manufacturer more than the filter.
Many cars use PWM to control fuel pump speed, but this is the first I've seen that has a dedicated bare shield ground wire wrapped around the power wire 🤔
Hi from the UK 🇬🇧! Used to get this all the time on Citroën, lost count of harness repairs especially across the front in the engine bay, the bits of gravel and sand would find their way into the insulation and grind through to the copper until it turned green and disintegrated!
put 10 amps through it and watch with the thermal camera, you'll see exactly where to unwrap the harness. I had a similar problem with a late 80's Range Rover, error codes and blown fuses like it was possessed. Unwrapped the harness and all of the wiring insulation had degraded into something with the consistency of Playdough crafting clay. Replaced the whole harness.
Ah, yeah. 1980's cars were prone to that. Volvo 740/760 and 240 come to mind. I think it was because car manufacturers started to use other type of wiring insulation (bio degradeable?)
@@jfv65 They might have done what Ford did and make the insulation from soy instead of petroleum. The little creatures of the world loved to chew on that stuff.
Great job! I've found one of the most difficult issues to troubleshoot was when wires from unrelated systems were in contact with each other. I didn't make sense, and it did not match the wiring diagram, because the connection was not supposed to exist. And people wonder why it took so long to figure out!
At other applications, you'll see some ceramic capacitors directly soldered to the motor contacts, for clamping down on that interference. Sometimes, you'll even see some inductors. All of that could be safely tucked away in the sealed fuel pump motor case, in the tank, far away from water. But Ford rather uses shielding, apparently. But not a properly shielded cable, because that would be expensive. Just wrap it with some grounded metal wire mesh tape and wrap that with that protective tubing that wicks up water. When dry, it is an abrasive mix of metal wire mesh and salt crystals, nicely grinding away insulation, by means of the car's vibrations. At the first tiny compromise of the insulation and when wet, electrolysis will occur. The process will accelerate and soon you'll have a nice short capable of blowing 20A fuses. Great design, Ford.
Road Salt water spray under vehicle permeated harness and pink wire is hot while pump is running becomes a galvanic anode dissolving the copper at some pinhole in plastic .18 years of salt immersion. Not to bad. Good fix with the scope on a rope old school test light.
That is a crazy one. You got to love the salt and calcium on our winter roads. I didn't see any in there inside the electrical tape, but water intrusion there could also added to that problem. At least minimal parts were required to fix.
Gotta love the technical jargon, "WTF?"!🤣 As someone who has picked away at more than one ancient, crusty, rust bucket, I can well understand the frustration and elation upon discovering the faulty wire! I've learned that you can never, never, never assume because something appears ok, that it in fact is. Great vid, guys! 👍
I had the same problem on my 2014 Ford E450. I ended up running new wires from the fuel pump module to the fuel pump. I no longer have shielding on the wires and everything works just fine.
One day I had a older Chevy Cruze that wouldn’t crank. But, move the main power wire from the battery a certain way, it would start. But drive it out of the shop it would die. Very Long story short, found that a electric power steering wire was rubbing on a CAMBUS wire. Somebody who had been working on it didn’t secure the wiring harness and it was rubbing together. One of those things you’d had to be there to understand/appreciate. Was super proud of my self for finding it and have solved other weird issues based off of this. Wish I had your knowledge of pico scopes and amp clamps. Would of helped a lot of some of these problems I’ve seen coming into the shop.
Turned on the PC after getting my coffee and here you are. This is going to be a good day. So were those wires truly shielded? As in RF shielded? It almost looked like regular tape was holding it together. Thanks!
Its very funny when some of those old mechanics, with many years of experience I might add, are blown away, Amazed and other adjectives from the skills that Ivan has. Entertainment at its best for me. Thanks Ivan. I laughed so hard.
The first thing I thought when we looked at the diagram was, it's shorted to the shield. The second thing I thought was WHY the shield in the first place. Coincidentaly, I had a problem with shielding shorting to data lines in a canbus yesterday. Not a car, it was a boiler.
Ivan, I swear on my life what you just said you have never seen, I had in my Saturn, which I suspected had been tampered with...and for 13 years it read that it had a 2.2L engine on EVERY SINGLE PIECE OF 30 pages of service history...until it somehow read 2.0L at the point at which it stopped passing emissions. Also, I kept having the MIL set when I turned the steering wheel, opened it up and saw the same type of goo connecting a pink and black set of wires...THANK YOU SO MUCH.
In the northern area often ice causes problems. That is water gets in harness and freeze. This makes a wire loom ice hard for a section. That hard section then vibrates and wears out wires where the ice stops. Ironically the wire loom makes this worse because it holds the water inside loom to freeze and making icicle. Note, even having small pieces of ice with sharp edges cause problems.
Used to run into similar faults with communication cables that would get wet. Turns out that some vinyl insulation , at a molecular level, allows water to enter. It's water resistant, not water proof. So when it is immersed for long periods enough water will penetrated the insulation to cause a galvanic reaction, usually to ground.
THHN (vinyl insulation) wire absorbs water when the outer coating is nicked. It causes very odd problems. It is not recommended for wet environments. I'm not sure how prevalent it is in automotive.
Nice one. A bit off topic but my 97 Celica GT Convertible, 231,000 miles started hesitating and bucking, only very slightly. Changed the fuel filter, no improvement. Tested for blown head gasket, all OK. Then I put my thinking cap on. I thought about some of the stuff I had replaced- plug wires, spark plugs, distributor cap etc. Remembered some of your videos where the problem was with the replaced part. The new wires and plugs I put on were expensive NGK, but the distributor cap purchased from Amazon, supposedly a Bosch, arrived in a clear plastic bag with no markings on the cap, nothing. Luckily I kept the old Denso cap which I cleaned and put back on and you can probably guess the car runs like a clock again. The moral of the story, try and buy quality parts and keep the part you replaced just in case!
Love watching your thought processes as you troubleshoot. I've been pretty good at keeping my old junk running and enjoy troubleshooting so I bought a 2013 Civic Hybrid that is effectively an electrical brick. (Mechanically it runs great.) I may have bitten off a bit more than I can chew at this point, but I'm going to fix it. (Though I'll probably end up with $3000 worth of new diagnostic tools to help reduce my already expensive parts cannoning.) Thanks again! Aaron S Rose
I just bought a meter like yours on Amazon to check for DC Amps. I had a Robot blowing out a fuse for the 24v DC. My old fluke meter doesn't have DC Amp draw. I had to do it the old fashion was of changing out some parts.
I had one like this with an ‘05 mountaineer. Someone pierced the power wire and never sealed it backup. Corroded the wire and crank no start. Brother in law loaded the parts cannon before he called me to help. That was a fun one.
Excellent diagnostic!! 20 amp fuse #26. I guess heavy draw of module and fuel pump in operation plus the 1 amp short draw, pushed it over the 20 amps? I would have thought it would have a higher draw at the short.
Reminds me of the way 2010-2017 Navistar International day cab road tractors were with their rear ABS wires.....no shield wire, but pretty amazing how the split loom over the wire harness managed to rub through the insulation on the wires and the road salt just turned the exposed wires to green crusty gunk. Made it even more unbelievable that on the later model day cabs that they had a really long harness (guessing they used the same harness on short day cabs and the longer trucks with sleepers) for the ABS that at the factory they folded over itself.....and then wonder why the ABS wiring had issues
Wow, salt killed the wires with insulation wrapped around? Wow. Unreal. I seem that guy cutting towards him. I thought that would slice him lol. Great diagnosis! Nitty-gritty of the work involved! Gotta love the amp clamp and Light test! Awesome video!
I had a '91 Chevy 2500 company truck that would flicker the lights and dash gauges when making a left turn. It finally blew the main accessory fuse at the battery positive terminal. I followed the accessory wire and found it was tangled in the passenger side front coil spring seat. The GM assembly guy must have needed to take a crap and rushed through the wire harness installation.
I made a little device to add a buzzer and light to a shorted wire. It hooked up through the fuse box, and it added enough resistance to the circuit to allow it to continue flowing current without blowing its own fuse. Then it's just a matter of wiggling and listening, the buzzer allowed one to stop staring at the bulb. Add that to a thermal imager and you'll find it quickly. I really liked the idea of sending a radio signal down those wires, but guys who use them every day point out that they are not as great as you think they should be. For example in this case, with a Faraday cage around the involved wires, you will lose the signal because of the cage.
The PWM from the fuel pump controller is causing radiated emissions (EMI) (anything with a fast switching rate will create RE) they needed to clamp it to the chassis. Ironically, I am testing a new PWM fuel pump controller for radiated emissions and Radiated immunity as we speak. They are noisy devices from an EMC stand point. Also, I recommend a seam ripper to split conduit (can found in the sewing aisle of any store). That utility knife is just looking for someone to send to the hospital.
The truck looks like it is well taken care of. If that truck had that issue with the factory wiring why are there not more Fords out there with that problem. Really nice find....👍
SWEET! When you said sweet, that reminded me of dudes I use to know--whereas one dude would say sweet for everything, and the other dude would say basically for everything. Every sentence had a sweet or basically inserted in their conversations.
Just in case it helps somebody- there are tone generators and hand held amplifiers that are used in the telecom industry. They are used to send a signal through a wire so it's physical location can be traced. If you're having to track down wires in a harness and you aren't sure the diagram is correct, they are very helpful. Seems like that might work here.
Great job Ivan and Al. Al, good thing there wasn't any gas leaks with that cig in your lips. That's why they say smoking "can be hazardous to your health." Think I'll wire up some test lights this afternoon. Thanks for Sharing!
That is a weird one! This wasn't the weirdest one i had but 1990 E-350 cut-away van kept blowing the fuel pump fuse. It ended up being in the three wire connector the hooked to the sending unit. I bought a brand new connector from Ford and it was shorted just like the old one. I ended up just making my own up and fixed the problem.
My wife had a 2001 Sebring that intermittently blew the 10 amp ignition fuse causing the car to shut down like the key was turned off. Turns out that 2 connectors under the dash had their locations swapped compared to the All Data sketch. This caused a harness to run up against the sharp edge of a support it went thru. I was lucky to find it.
This one reminded me of the old toyota cressidas, the single wire o2 sensor had a grounded shield around its wire, the shield would cut into the wire keep the voltage at zero and set a code.
I have seen something similar on a 7.3 diesel. They have shielded wires for the injectors and one has rubbed through and was shorting the signal to ground.
I once came across a late 80's Camaro that would blow the fuel pump fuse when the driver door was slammed closed. It took awhile to find the bad spot in the harness by the A pillar. Easy repair once it was found.
it is at a mount point so rubbing is possible... but not likely??? LOL... did insulation looked charred at all?? maybe a winter freeze caused fuel pump to be a large draw that melted the insulation to the shielding then over time corroded? maybe at the factory when that harness was created some metal got locked into that location and corroded? that seems more plausible
shielded wiring to keep it from spewing RF noise. why do they do that? some people like to listen to AM radio stations still, as well as ham operators and other people around the vehicles. same reason for resistor spark plugs and resistance wires, only back then it interfered with everything used daily by many since it was all analog signal and poorly filtered (tv, radio, other)
salt water is probably getting into the connector and then wicking inside of the wire insulation. i've seen this happen before with cam sensor wiring. oil wicks into the insulation all the way to the pcm and into the pcm. never seen that with salt though!
looks like it rubbed through right at or near the harness holder, it's common to get chaffing and wear through at holders and radius bends. vibration probably had it rubbing against the bare shield wire or against the flex-loom, I've found bad wires like that all over the place on vehicles and other equipment.
That almost looks like water block wiring similar to direct burial. That white wrap is supposed to keep the water out. I’m not sure that is salt you are seeing. Nice find!
Its just Crazy how Salt and moisture finds there way into a Wiring Harness. Talk about finding a needle in a hay stack...WOW...Great Job finding it. .The Gentleman that you was working with is a Perfect example of an Old School Mechanic. LOL...HAHA..Whenever you walk into a Garage and you hear words like this you know 1st They been a mechanic for years, and 2nd Hes a Good Mechanic...LOL..HAHA...If You walk into a Garage and dont hear those words ever.RUN RUN as fast as you can. Because They havent been doing mechanic work long enough or there not HUMAN....LMAO....LOL..HAHA.Great Video. Other good mechanics know what Im talking about...LOL...HAHA..
In the South, where we have no salted roads, the pump control module is bolted to the frame near one of the rear tires, and due to a terrible design, the moisture gets trapped between the module and the frame and the module corrodes away, allowing water to enter it which causes various shorts to occur, as well as odd ignition, fuel pump relay, and fuel pump behavior. Down here, a lot of perfectly good fuel pumps have been replaced due to bad fuel pump control modules. These modules cost about a tenth or less of the cost replacing an in-tank fuel pump, and the modules are replaced at the same time as part of good shop practices. The problem goes away, and the shop has another pump it can clean up and sell.
Ivan I saw problems like this in the 1980's ground circuits spliced midstream and wrapped with friction tape, no reference to the location of the splice on the wiring diagrams, holes in the insulation of wires wrapped ,damaged for no reason. almost like the damage was done intentionally in the manufacture of the harness. It never ends with these manufactures, and their pointless to the fact the vehicle will run in the salt when designing. thank god I'm retired.
You look at the corrosion on the frame you know the environment during winter is wet and messy and that plastic sleeve with a crack in it so it can be wrapped after the harness is finished is no protection. If they put a shrink-wrap on it while the harness was being built, that might have been sufficient, routing it through the fender out of the elements would also work but that adds complexity and cost.
That is worthy of a recall by Ford! In the electricity industry we had an overhead service cable called "Neutral Screened" cable. The neutral return was a bare wire wrapped around the insulation of the active wire, all covered with insulation so it looked like one circular cable. I guess it was deemed less of an eye sore. Where you terminated the cable at the house connection and also on the power pole, you had to unwrap the neutral, sleeve it with insulation then make your connection. Fast forward many years later, maybe decades, (who knows - it was already up when I came across), it was failing at the pole end because it is exposed to the elements and water/moisture would make its way up the neutral strands, pool in the droop of the cable and slowly turn the copper into white powder. As I am sure with your electrical engineering background Ivan, you know that this would cause fluctuations in the power supply, most noticeable as flickering lights, and if left unchecked would lead to shocks & tingle or worse due to the CMEN system of earthing (if your country uses that system). It is much better to have all conductors have their own insulation!
@@dancarney106 The reason for it being around a starter cable is because as Ivan has shown many times doing cylinder balance tests with the PICO, the current is not smooth but full of spikes which would again generate noise. That said, the frequency generated is rather low so shielding that seems kinda overkill.
There is a vulnerability of harness construction (manufacture) if the harness is subjected to salt spray, like in the rust belt. The problem is any mistake in manufacture of the harness in nicking or slicing insulation will result in corrosion which can result in a short like this in a harness that uses a shield. The shield and the shield drain wire are used to reduce pump switching noise created EMI. Really the fuel pump power control for a PWM modulated pump motor should be at the pump. If you send these switching power currents through a long harness you will probably need a shield grounded at the source end to pass vehicle EMC. To prevent salt spray from invading the harness, it should be sealed.
Actually not. It's only the fumes that go up. We used to throw lit cigarettes into an open bucket of fuel to scare the bejesus outta youn'uns. The cigarettes were extinguished everytime. 😱
let's hear it for soy based wire insulation! The weirdest wiring problem I had was a driver was driving her Ford diesel pickup on the freeway and had cruise selected, a car pulled in front and she tapped the brake to disengage cruise. It did not disengage, she hit the brakes to slow from hitting the car and it slowed but when she lifted it went into resume speed. She disconnected cruise at the switch and all was ok for then. I tried to duplicate and it did the sae thing, the tuck was under warranty and taken to a Ford dealer, the service guy said it was impossible to have that happen, I invited him to drive the truck he did and almost dirtied his pants when it did the same thing but with almost catastrophic consequences. The tech also said it was impossible and was treated to the same eye opening event. The techs checked everything and could not understand why it will not disengage with the brake pedal disengage. I went over the schematics and found that the brake to cruise disengage got it's 12 volts from the right brake light circuit, the right brake light fuse was blown in checking the wiring I found a wire bundle that goes through the right rear of the bed was chaffed and shorted the right brake wire. but still there should be a vacuum break to disconnect the circuit. nobody at the dealer could figure out what was wrong, i was put in contact with a factory brake engineer and ha poo pooed the whole thing and said the vacuum system would disconnect when the pedal was depressed. I went over the schematics with him and told him there was no vacuum break built into the 1997 ford F-350 crew cab 7.3 Diesel truck system. He insisted that there was and I told him to prove it. He couldn't. He did find out that the wire bundle through the frame and bed on those trucks was a problem with a lot of trucks. We fixed the wire and rerouted them wrapped with a teflon sheet ( I am a master mechanic and a jet acft mechanic and use this technique on the F-16's) all was resolved. bit there was no backup vacuum break disconnect.
04 explorer is weird. Both Ive driven while actually die while driving if you Have cruise control on and hold down the decel to under like 35 mph. I guess bad programming lol
A lot of CATERPILLAR wiring uses this type of shielding as it has analogue to digital convertors in circuits as part of wiring harnesses, a LOT of mining operations use ground water which generally is salty for dust suppression and the to top it off in iron ore mining most the little rocks that sit in places to rub on harnesses or get into harnesses are in excess of 50% iron in content, an electricians hell 😀, a common comment is "oh we've got a rub through somewhere, novices look for external rub marks only 😆 they guy from UK comment about little rocks in harnesses on Citroen's was a de ja vu moment
That is a Faraday shield to reduce capacitively coupled fuel pump brush noise from interfering with radio reception.
I have a Faraday pouch for my Tundra key. Push button start is easy to steal.
I have a Friday too😄😄
agreed.
Other way around... It's to stop outside interference from making it's way to the fuel pump. As they do that to prevent the fuel pump from burning up... Why it's driven by the fuel pump module.
And at $350.00 for the pump. Then labor to replace them. Seems cheaper to repair the wire...
@@WizzRacing that’s ridiculous.
Just guessing but since the radio amplifier is in the RR corner there may have been issues with EMF coming from the fuel pump which could explain the need for shielding.
Not only from the fuel pump, but I think primarily from the fuel pump driver, since it uses PWM the signal will be a square wave with a lot of high frequency components. Which is why the wires from the driver to the fuel pump should be as short as possible.
Correct. Shielding is common when electrical noise is a concern. Usually it's used when the wire might pick up noise, but it's also used to prevent the wire from radiating noise.
@T.J. Kong you can't use just a capacitor to filter high frequencies from a PWM signal. What you need is a LC filter to make an average DC voltage from the AC signal. But then you've just created a plain old DC-DC buck converter. Could they do that to filter the noise? Yes, but coils and capacitors cost money, and if you can get away with not using them, they won't. It's debatable whether installing the shielding over the cable harness cost the manufacturer more than the filter.
@T.J. Kong A cap would increase the instantaneous current the transistors would have to supply.
Many cars use PWM to control fuel pump speed, but this is the first I've seen that has a dedicated bare shield ground wire wrapped around the power wire 🤔
Hi from the UK 🇬🇧! Used to get this all the time on Citroën, lost count of harness repairs especially across the front in the engine bay, the bits of gravel and sand would find their way into the insulation and grind through to the copper until it turned green and disintegrated!
put 10 amps through it and watch with the thermal camera, you'll see exactly where to unwrap the harness. I had a similar problem with a late 80's Range Rover, error codes and blown fuses like it was possessed. Unwrapped the harness and all of the wiring insulation had degraded into something with the consistency of Playdough crafting clay. Replaced the whole harness.
Good advice thank you
Ah, yeah. 1980's cars were prone to that. Volvo 740/760 and 240 come to mind.
I think it was because car manufacturers started to use other type of wiring insulation (bio degradeable?)
@@jfv65 They might have done what Ford did and make the insulation from soy instead of petroleum. The little creatures of the world loved to chew on that stuff.
Better yet, put 100 amp fuse and watch for the glowing sheet metal
Trusty ole smoke test
Great job! I've found one of the most difficult issues to troubleshoot was when wires from unrelated systems were in contact with each other. I didn't make sense, and it did not match the wiring diagram, because the connection was not supposed to exist. And people wonder why it took so long to figure out!
I've seen a single strand of wire poke through it's and another wires insulation and take out a can network
At other applications, you'll see some ceramic capacitors directly soldered to the motor contacts, for clamping down on that interference. Sometimes, you'll even see some inductors. All of that could be safely tucked away in the sealed fuel pump motor case, in the tank, far away from water. But Ford rather uses shielding, apparently. But not a properly shielded cable, because that would be expensive. Just wrap it with some grounded metal wire mesh tape and wrap that with that protective tubing that wicks up water. When dry, it is an abrasive mix of metal wire mesh and salt crystals, nicely grinding away insulation, by means of the car's vibrations.
At the first tiny compromise of the insulation and when wet, electrolysis will occur. The process will accelerate and soon you'll have a nice short capable of blowing 20A fuses.
Great design, Ford.
Ivan you did it again showing us how important it is to read wiring diagrams and back tracking thanks again
Road Salt water spray under vehicle permeated harness and pink wire is hot while pump is running becomes a galvanic anode dissolving the copper at some pinhole in plastic .18 years of salt immersion. Not to bad.
Good fix with the scope on a rope old school test light.
That is a crazy one. You got to love the salt and calcium on our winter roads. I didn't see any in there inside the electrical tape, but water intrusion there could also added to that problem. At least minimal parts were required to fix.
Gotta love the technical jargon, "WTF?"!🤣 As someone who has picked away at more than one ancient, crusty, rust bucket, I can well understand the frustration and elation upon discovering the faulty wire! I've learned that you can never, never, never assume because something appears ok, that it in fact is. Great vid, guys! 👍
I had the same problem on my 2014 Ford E450. I ended up running new wires from the fuel pump module to the fuel pump. I no longer have shielding on the wires and everything works just fine.
One day I had a older Chevy Cruze that wouldn’t crank. But, move the main power wire from the battery a certain way, it would start. But drive it out of the shop it would die. Very Long story short, found that a electric power steering wire was rubbing on a CAMBUS wire. Somebody who had been working on it didn’t secure the wiring harness and it was rubbing together. One of those things you’d had to be there to understand/appreciate. Was super proud of my self for finding it and have solved other weird issues based off of this. Wish I had your knowledge of pico scopes and amp clamps. Would of helped a lot of some of these problems I’ve seen coming into the shop.
Turned on the PC after getting my coffee and here you are. This is going to be a good day. So were those wires truly shielded? As in RF shielded? It almost looked like regular tape was holding it together. Thanks!
Its very funny when some of those old mechanics, with many years of experience I might add, are blown away, Amazed and other adjectives from the skills that Ivan has. Entertainment at its best for me. Thanks Ivan. I laughed so hard.
Nice find Ivan. Don't see too many guys working with a cigarette in their mouths anymore.
... while working on the fuel pump...
Great job. I have seen 1990s Volvos where the insulation just disintegrated and left wire touching.
The first thing I thought when we looked at the diagram was, it's shorted to the shield. The second thing I thought was WHY the shield in the first place. Coincidentaly, I had a problem with shielding shorting to data lines in a canbus yesterday. Not a car, it was a boiler.
good job Al, George, Chuck and Ivan
Ivan, I swear on my life what you just said you have never seen, I had in my Saturn, which I suspected had been tampered with...and for 13 years it read that it had a 2.2L engine on EVERY SINGLE PIECE OF 30 pages of service history...until it somehow read 2.0L at the point at which it stopped passing emissions. Also, I kept having the MIL set when I turned the steering wheel, opened it up and saw the same type of goo connecting a pink and black set of wires...THANK YOU SO MUCH.
In the northern area often ice causes problems. That is water gets in harness and freeze. This makes a wire loom ice hard for a section. That hard section then vibrates and wears out wires where the ice stops. Ironically the wire loom makes this worse because it holds the water inside loom to freeze and making icicle. Note, even having small pieces of ice with sharp edges cause problems.
Used to run into similar faults with communication cables that would get wet. Turns out that some vinyl insulation , at a molecular level, allows water to enter. It's water resistant, not water proof. So when it is immersed for long periods enough water will penetrated the insulation to cause a galvanic reaction, usually to ground.
THHN (vinyl insulation) wire absorbs water when the outer coating is nicked. It causes very odd problems. It is not recommended for wet environments. I'm not sure how prevalent it is in automotive.
I can see that. We think of plastics as water barriers. I found out a while back that's not exactly true. Plastics are, in varying degrees, permeable.
Nice one. A bit off topic but my 97 Celica GT Convertible, 231,000 miles started hesitating and bucking, only very slightly. Changed the fuel filter, no improvement. Tested for blown head gasket, all OK. Then I put my thinking cap on. I thought about some of the stuff I had replaced- plug wires, spark plugs, distributor cap etc. Remembered some of your videos where the problem was with the replaced part. The new wires and plugs I put on were expensive NGK, but the distributor cap purchased from Amazon, supposedly a Bosch, arrived in a clear plastic bag with no markings on the cap, nothing. Luckily I kept the old Denso cap which I cleaned and put back on and you can probably guess the car runs like a clock again. The moral of the story, try and buy quality parts and keep the part you replaced just in case!
ngk wires are junk buy them at the dealer l1 master car and truck
@@juanrodriguez-ry6yt NGK products are rated very highly but of course you are entitled to your opinion.
@@robbflynn4325 nothing beats the original wires i've had to replace plug wires
Great job as always. When the video first came on and we saw the lift. I was momentarily over joyed for you thinking you got a lift finally!
Had something similar on a chevy cavalier. Abs wires were all rotted. Looked absolutely fine on the outside but did not pass the old tug test
Love watching your thought processes as you troubleshoot. I've been pretty good at keeping my old junk running and enjoy troubleshooting so I bought a 2013 Civic Hybrid that is effectively an electrical brick. (Mechanically it runs great.) I may have bitten off a bit more than I can chew at this point, but I'm going to fix it. (Though I'll probably end up with $3000 worth of new diagnostic tools to help reduce my already expensive parts cannoning.) Thanks again! Aaron S Rose
I'm so glad I live in a non-salted-road state. Nice work.
I just bought a meter like yours on Amazon to check for DC Amps. I had a Robot blowing out a fuse for the 24v DC. My old fluke meter doesn't have DC Amp draw. I had to do it the old fashion was of changing out some parts.
KRAZY! Glad you found it. You, Wes, Eric, the Wizard and Ray are great sources of info and entertainment. Many thanks.
When Al gets to cutting on something, he doesn’t stop.
He got a little excited He swore it happens lol 🤣🤣🤣
I had one like this with an ‘05 mountaineer. Someone pierced the power wire and never sealed it backup. Corroded the wire and crank no start. Brother in law loaded the parts cannon before he called me to help. That was a fun one.
Excellent diagnostic!! 20 amp fuse #26. I guess heavy draw of module and fuel pump in operation plus the 1 amp short draw, pushed it over the 20 amps? I would have thought it would have a higher draw at the short.
The 1 amp draw was controlled by my test light lol. It was a full short to ground 👌😁
Makes sense with the explanation. Thanks
Reminds me of the way 2010-2017 Navistar International day cab road tractors were with their rear ABS wires.....no shield wire, but pretty amazing how the split loom over the wire harness managed to rub through the insulation on the wires and the road salt just turned the exposed wires to green crusty gunk. Made it even more unbelievable that on the later model day cabs that they had a really long harness (guessing they used the same harness on short day cabs and the longer trucks with sleepers) for the ABS that at the factory they folded over itself.....and then wonder why the ABS wiring had issues
Great job , could it have been damaged in the past my someone reinstalling the spare wheel with a jack or lift?
Wow, salt killed the wires with insulation wrapped around? Wow. Unreal. I seem that guy cutting towards him. I thought that would slice him lol. Great diagnosis! Nitty-gritty of the work involved! Gotta love the amp clamp and Light test! Awesome video!
I had a '91 Chevy 2500 company truck that would flicker the lights and dash gauges when making a left turn. It finally blew the main accessory fuse at the battery positive terminal. I followed the accessory wire and found it was tangled in the passenger side front coil spring seat. The GM assembly guy must have needed to take a crap and rushed through the wire harness installation.
Nice!
I made a little device to add a buzzer and light to a shorted wire. It hooked up through the fuse box, and it added enough resistance to the circuit to allow it to continue flowing current without blowing its own fuse. Then it's just a matter of wiggling and listening, the buzzer allowed one to stop staring at the bulb. Add that to a thermal imager and you'll find it quickly. I really liked the idea of sending a radio signal down those wires, but guys who use them every day point out that they are not as great as you think they should be. For example in this case, with a Faraday cage around the involved wires, you will lose the signal because of the cage.
The PWM from the fuel pump controller is causing radiated emissions (EMI) (anything with a fast switching rate will create RE) they needed to clamp it to the chassis. Ironically, I am testing a new PWM fuel pump controller for radiated emissions and Radiated immunity as we speak. They are noisy devices from an EMC stand point. Also, I recommend a seam ripper to split conduit (can found in the sewing aisle of any store). That utility knife is just looking for someone to send to the hospital.
Hook blade used for cutting asphalt (roofing shingles) is a good option.
The truck looks like it is well taken care of. If that truck had that issue with the factory wiring why are there not more Fords out there with that problem. Really nice find....👍
SWEET! When you said sweet, that reminded me of dudes I use to know--whereas one dude would say sweet for everything, and the other dude would say basically for everything. Every sentence had a sweet or basically inserted in their conversations.
Wow now that's crazy !! A salt catcher by design. Great vid and case study. Something to keep in mind for the future.
Great work guys!
I found the short in my car without any tools. Just wiggled wires for days! LoL
Just in case it helps somebody- there are tone generators and hand held amplifiers that are used in the telecom industry. They are used to send a signal through a wire so it's physical location can be traced. If you're having to track down wires in a harness and you aren't sure the diagram is correct, they are very helpful. Seems like that might work here.
Great job Ivan and Al. Al, good thing there wasn't any gas leaks with that cig in your lips. That's why they say smoking "can be hazardous to your health." Think I'll wire up some test lights this afternoon. Thanks for Sharing!
That is a weird one! This wasn't the weirdest one i had but 1990 E-350 cut-away van kept blowing the fuel pump fuse. It ended up being in the three wire connector the hooked to the sending unit. I bought a brand new connector from Ford and it was shorted just like the old one. I ended up just making my own up and fixed the problem.
My wife had a 2001 Sebring that intermittently blew the 10 amp ignition fuse causing the car to shut down like the key was turned off. Turns out that 2 connectors under the dash had their locations swapped compared to the All Data sketch. This caused a harness to run up against the sharp edge of a support it went thru. I was lucky to find it.
That is a weird one for sure Ivan! Thanks for posting!
You are the best, i am diagnostic man too, 20year, i live in Israel, love your channel:)
Greetings from Israel.
New video just in time for my lunch break 😀 thanks Ivan
Cool find! Love when the exact spot is found!
This one reminded me of the old toyota cressidas, the single wire o2 sensor had a grounded shield around its wire, the shield would cut into the wire keep the voltage at zero and set a code.
Gee, @4:10 something was burning....glad you guys are safety conscious.
That smoke was from the guy's cig, genius.
@@notsureigaf It was a joke - sorry you did not get it
Brilliant! each and every time.
I have seen something similar on a 7.3 diesel. They have shielded wires for the injectors and one has rubbed through and was shorting the signal to ground.
No wonder Keith moved!!! LOL good video Ivan thanks !
Ivan is the man for the job no doubt
Hahaha some real reactions great job Ivan…. Cars never cease to amaze me with some of the problem they encounter
Another interesting chapter in the notebook..👍
See that from time to time on aircraft wiring ,which use a lot of metal shielding.
I really enjoy all your videos, keep up the great work 👍.
I once came across a late 80's Camaro that would blow the fuel pump fuse when the driver door was slammed closed. It took awhile to find the bad spot in the harness by the A pillar. Easy repair once it was found.
it is at a mount point so rubbing is possible... but not likely??? LOL... did insulation looked charred at all?? maybe a winter freeze caused fuel pump to be a large draw that melted the insulation to the shielding then over time corroded? maybe at the factory when that harness was created some metal got locked into that location and corroded? that seems more plausible
Time to wrap it in split loom and liquid tape. Good find and fix.
shielded wiring to keep it from spewing RF noise. why do they do that? some people like to listen to AM radio stations still, as well as ham operators and other people around the vehicles.
same reason for resistor spark plugs and resistance wires, only back then it interfered with everything used daily by many since it was all analog signal and poorly filtered (tv, radio, other)
salt water is probably getting into the connector and then wicking inside of the wire insulation. i've seen this happen before with cam sensor wiring. oil wicks into the insulation all the way to the pcm and into the pcm. never seen that with salt though!
looks like it rubbed through right at or near the harness holder, it's common to get chaffing and wear through at holders and radius bends.
vibration probably had it rubbing against the bare shield wire or against the flex-loom, I've found bad wires like that all over the place on vehicles and other equipment.
That almost looks like water block wiring similar to direct burial. That white wrap is supposed to keep the water out. I’m not sure that is salt you are seeing. Nice find!
Can you show how you hook a test light up to find a short
Its just Crazy how Salt and moisture finds there way into a Wiring Harness. Talk about finding a needle in a hay stack...WOW...Great Job finding it. .The Gentleman that you was working with is a Perfect example of an Old School Mechanic. LOL...HAHA..Whenever you walk into a Garage and you hear words like this you know 1st They been a mechanic for years, and 2nd Hes a Good Mechanic...LOL..HAHA...If You walk into a Garage and dont hear those words ever.RUN RUN as fast as you can. Because They havent been doing mechanic work long enough or there not HUMAN....LMAO....LOL..HAHA.Great Video. Other good mechanics know what Im talking about...LOL...HAHA..
In the South, where we have no salted roads, the pump control module is bolted to the frame near one of the rear tires, and due to a terrible design, the moisture gets trapped between the module and the frame and the module corrodes away, allowing water to enter it which causes various shorts to occur, as well as odd ignition, fuel pump relay, and fuel pump behavior. Down here, a lot of perfectly good fuel pumps have been replaced due to bad fuel pump control modules. These modules cost about a tenth or less of the cost replacing an in-tank fuel pump, and the modules are replaced at the same time as part of good shop practices. The problem goes away, and the shop has another pump it can clean up and sell.
Wow Ivan saved a Ford Exploder from the Scrap Heap! 🤭
Ivan I saw problems like this in the 1980's ground circuits spliced midstream and wrapped with friction tape, no reference to the location of the splice on the wiring diagrams, holes in the insulation of wires wrapped ,damaged for no reason. almost like the damage was done intentionally in the manufacture of the harness. It never ends with these manufactures, and their pointless to the fact the vehicle will run in the salt when designing. thank god I'm retired.
Nice place to put that harness, looks like it's very close to the wheel well.....k
You look at the corrosion on the frame you know the environment during winter is wet and messy and that plastic sleeve with a crack in it so it can be wrapped after the harness is finished is no protection. If they put a shrink-wrap on it while the harness was being built, that might have been sufficient, routing it through the fender out of the elements would also work but that adds complexity and cost.
That is worthy of a recall by Ford! In the electricity industry we had an overhead service cable called "Neutral Screened" cable. The neutral return was a bare wire wrapped around the insulation of the active wire, all covered with insulation so it looked like one circular cable. I guess it was deemed less of an eye sore. Where you terminated the cable at the house connection and also on the power pole, you had to unwrap the neutral, sleeve it with insulation then make your connection. Fast forward many years later, maybe decades, (who knows - it was already up when I came across), it was failing at the pole end because it is exposed to the elements and water/moisture would make its way up the neutral strands, pool in the droop of the cable and slowly turn the copper into white powder. As I am sure with your electrical engineering background Ivan, you know that this would cause fluctuations in the power supply, most noticeable as flickering lights, and if left unchecked would lead to shocks & tingle or worse due to the CMEN system of earthing (if your country uses that system). It is much better to have all conductors have their own insulation!
Great job Al!
When shielding actually becomes the problem! Was Ford having interference problems with the pump operation to come up with that "solution"? Crazy!
@@dancarney106 never seen shielded fuel pump wires
@@dancarney106 The amount current is not the reason for the shielding. It's because the current is pulse-width modulated.
@@PineHollowAutoDiagnostics Ivan it depends on what other wires they are bundled with.
Paul (in MA)
@@dancarney106 Anyplace with snow and ice on the road. lol Calcium chloride is just dandy for chassis and cabling......
@@dancarney106 The reason for it being around a starter cable is because as Ivan has shown many times doing cylinder balance tests with the PICO, the current is not smooth but full of spikes which would again generate noise. That said, the frequency generated is rather low so shielding that seems kinda overkill.
Crazy! Thanks Ivan!
There is a vulnerability of harness construction (manufacture) if the harness is subjected to salt spray, like in the rust belt. The problem is any mistake in manufacture of the harness in nicking or slicing insulation will result in corrosion which can result in a short like this in a harness that uses a shield. The shield and the shield drain wire are used to reduce pump switching noise created EMI. Really the fuel pump power control for a PWM modulated pump motor should be at the pump. If you send these switching power currents through a long harness you will probably need a shield grounded at the source end to pass vehicle EMC. To prevent salt spray from invading the harness, it should be sealed.
Great video Ivan. Happy birthday
Thank you 🙂
@@PineHollowAutoDiagnostics You're Welcome
Nice catch
Smorking near to fuel tank is danger
Actually not. It's only the fumes that go up. We used to throw lit cigarettes into an open bucket of fuel to scare the bejesus outta youn'uns. The cigarettes were extinguished everytime. 😱
Could you use the Flur camera to find it?
How was the shielding repaired?
I removed it completely 🤣
COOL! Now it sounds like a Real garage! X-D
That is freaking insane
Good morning
Morning!
I wonder if that explorer was in a Hurricane flood .
Wondering how the rest of the wiring is?
I had this happen on my brand new 2010 F150 back in 2010, was under warranty and they installed a different setup
at one point someone must have pierced the wires to test something back there
Vid shows factory wiring was not previously disturbed. Either a defect in the wire sheathing when it was MFG or the salt crystals caused abrasion.
yeah the test light is 🔥
LABOR RATE $100 phr, $150 if you watch, and $200 if you help.
Love
The "profanity ahead" precursor...lol😎👍🇨🇦
Hey Ivan and Big Al,
You do know that Ford circled their "mistake" don't you.... lnbo
That's a typical day up here in Canada. LOL
let's hear it for soy based wire insulation! The weirdest wiring problem I had was a driver was driving her Ford diesel pickup on the freeway and had cruise selected, a car pulled in front and she tapped the brake to disengage cruise. It did not disengage, she hit the brakes to slow from hitting the car and it slowed but when she lifted it went into resume speed. She disconnected cruise at the switch and all was ok for then. I tried to duplicate and it did the sae thing, the tuck was under warranty and taken to a Ford dealer, the service guy said it was impossible to have that happen, I invited him to drive the truck he did and almost dirtied his pants when it did the same thing but with almost catastrophic consequences. The tech also said it was impossible and was treated to the same eye opening event. The techs checked everything and could not understand why it will not disengage with the brake pedal disengage. I went over the schematics and found that the brake to cruise disengage got it's 12 volts from the right brake light circuit, the right brake light fuse was blown in checking the wiring I found a wire bundle that goes through the right rear of the bed was chaffed and shorted the right brake wire. but still there should be a vacuum break to disconnect the circuit. nobody at the dealer could figure out what was wrong, i was put in contact with a factory brake engineer and ha poo pooed the whole thing and said the vacuum system would disconnect when the pedal was depressed. I went over the schematics with him and told him there was no vacuum break built into the 1997 ford F-350 crew cab 7.3 Diesel truck system. He insisted that there was and I told him to prove it. He couldn't. He did find out that the wire bundle through the frame and bed on those trucks was a problem with a lot of trucks. We fixed the wire and rerouted them wrapped with a teflon sheet ( I am a master mechanic and a jet acft mechanic and use this technique on the F-16's) all was resolved. bit there was no backup vacuum break disconnect.
Impressive diagnosis. It can be very frustrating convincing people to take you seriously.
Stop calling them techs just because all they know is hooking up a scanner. 😄
It's like labeling a Parts guy who hooks up the scanner to your vehicle a TECH..😄😄😄
“How the fuck?!” … I concur! 👍😂😂😂
Ford has a long history of "better ideas".
How the F $#@ did you ever find that short. Love it.
04 explorer is weird. Both Ive driven while actually die while driving if you Have cruise control on and hold down the decel to under like 35 mph. I guess bad programming lol
A lot of CATERPILLAR wiring uses this type of shielding as it has analogue to digital convertors in circuits as part of wiring harnesses, a LOT of mining operations use ground water which generally is salty for dust suppression and the to top it off in iron ore mining most the little rocks that sit in places to rub on harnesses or get into harnesses are in excess of 50% iron in content, an electricians hell 😀, a common comment is "oh we've got a rub through somewhere, novices look for external rub marks only 😆 they guy from UK comment about little rocks in harnesses on Citroen's was a de ja vu moment