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Post by Peegoo 🏁 on Jan 3, 2021 14:34:00 GMT -5
Grab a beverage, kids. This is a protracted story.
The electric window on my '04 Toy Tacoma truck's driver door started acting up a few weeks ago; it's the switch and motor that gets the most use. It would motor down just fine, but sometimes it would refuse to go back up. Sometimes it would go halfway and stop. Other times, no problem.
I pulled the switch module out of the door and tested it, and the switches for all four windows were fine, along with the electric mirror controls and door lock switches. These switches carry higher current than what a meter uses, and that can mean a test like this not really reliable. An entire replacement module was $30 so I ordered one, it came in, and I swapped it in. All was good.
A week later the window started getting balky again, so I ordered a new window regulator ($23) which contains a little motor on a mounting bracket, a sector gear, and a two steel roller tracks. I parked the truck in the driveway and popped the door panel off, got the old regulator out and the new regulator in. Since I was testing the new motor and switch module, the ignition key had to be in the run position so I left the key on as I worked. Everything was working well, so I began reattaching the inner door panel...
I started smelling gasoline really strongly, so I peeked under the truck and there was a puddle of fuel on the driveway amidships, about two feet in diameter and more gas peeing out in a pretty happy little stream. GAH! I shut off the ignition and grabbed the fire bottle from the garage.
With the ignition off, the leak turned to a drip and then stopped, which told me it was a pressurized line from the in-tank fuel pump. What the heck? I sopped up the fuel and rinsed everything down with soapy water before even thinking about moving the truck. While the driveway dried off I got the door reassembled.
I crawled up under the truck (it's a Prerunner, plenty high to scoot under without ramps or jack stands) and I laid there in the fecal position looking around with a flashlight. Yeah, I know the term is "fetal," but the word I was thinking at the time made this the fecal position. Anyway, I found the problem: a short stiff rubber line about 16" long from the top of the fuel tank to a steel fuel line that runs forward to the fuel filter. It was leaking right through the rubber, in the middle of the tube. The connections were plastic quick releases, similar to a hydraulic line. I popped it off and got it to the shop to take a look under a bright light.
The fuel line is a soft rubber jacket over a hard polyurethane tube, and it looked like sabotage because there was deliberate mechanical damage to the jacket; it looked like someone had taken an ice pick to it. Several random-looking little gashes in an area about the size of a nickel. I begin turning over in my head all the names of ex-GFs that maybe had some grudge, and it was three days before Christmas, so maybe one of them was thinking of me over the holidays...
Hmmm. I sliced away the rubber jacket and there were matching gashes in the poly tube. I popped open the shop manual to get the name of the part, and as I walked to my car to zip over to the local Auto Zone, I saw a squirrel near another car on the street. TREE RATS! Bastages! It wasn't an ex. Squirrels have chewed the rubber hose on my gas grill more than once.
The Auto Zone guy said it was a specialty part (no aftermarket), so I rolled down to the Toyota dealer and spoke with the parts guy. He looked it up and said, "whoa...that part is 85 dollars." He looked at me to see if I was going to walk. I quickly thought I could sleeve on some reg'ler ol' 3/8" rubber fuel line...but I held fast and said, "I'm already here...may as well go with it." He poked at the keyboard and said, "let's see if they still supply them. Okay, this shows there are 73 of them in the US right now." My blood pressure... He added, "and there are five on the local area. You can pick it up tomorrow after 10 am." As he entered my name and phone number for the order, he asked if I had all my Christmas shopping done. "I just finished it three seconds ago," I replied.
When I picked up the part the first thing I did when I got home was wrap the replacement line with aluminum HVAC tape to discourage the tree rats next time they get up in there. With the part installed, everything works great and LUCKY ME I didn't have to drop the fuel tank to do it. I also replaced the fuel filter while I was under there and my hands were dirty.
They say things happen in threes, so any bets on the last item that's gonna pop up? I don't even want to think about it.
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Post by budg on Jan 3, 2021 15:02:05 GMT -5
Yeah mechanical work isn’t for the faint of heart that’s for sure . It’s like plumbing that way.
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Post by Taildragger on Jan 3, 2021 15:17:10 GMT -5
I remember the first time I worked on a car with computer: 1971 VW "Squareback" with early Bosch fuel injection that had developed an "on-again/off-again" miss. I'd always been half decent on cars with a carburetor, points/condensor ignition and no "sensors". I chased symptoms all over that damn car and never could resolve the problem. Took it to two different garages that specialized in VWs, one of which was run by a Wolfburg-trained German guy. They couldn't find the trouble either, partly because it only manifested itself intermittently. Was it the computer itself? A corroded connector someplace? Dunno.
Working on newer, computer-controlled cars got easier once it became possible for the consumer to "pull error codes", but working those first years of computerized cars was not much fun for the amateur, "shade-tree" mechanic. Or, at least, not for this one.
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Post by Peegoo 🏁 on Jan 3, 2021 15:20:56 GMT -5
Here's a good one: timing belt skipped a few teeth on a camshaft. The reason is hilarious.
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Tom B.
Halfnote
Posts: 54
Formerly Known As: Tom B.
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Post by Tom B. on Jan 4, 2021 20:03:14 GMT -5
You are fortunate enough to be able to figure out how to diagnose a problem, a skill that doesn't appear to be thoroughly taught at all automotive technician schools these days. We recently had a substantial roar seeming to arise from the rear of a preowned AWD SUV we had purchased, powertrain warranty still in effect. I suspected it was the rear differential. After eliminating tires, the dealer's diagnosis started with a front wheel bearing, not covered by warranty. I gave them the benefit of the doubt (noises can resonate within the cabin) and let them go ahead. Paid for it but it didn't solve the problem. Brought it back and they worked with corporate for the following work. Rear differential replacement got rid of the main roar, but it had been so loud that it masked another milder, but obvious, roar. $17k of parts later, 5 mos of loaner car, labor, all taken care of under warranty as it should be (except the 1st wheel brg that we paid for), we got our SUV back. Except for the hassle of 5 mos driving a substitute vehicle, we wound up with basically a new powertrain (everything but engine, axles and CV joints). But it was baffling and somewhat frustrating with each new diagnosis, parts order, replacement, and try again, all because of the approach often followed nowadays.
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Post by Peegoo 🏁 on Jan 4, 2021 22:58:42 GMT -5
Like Taildragger, I grew up working on engines that had breaker points and a rotor under a distributor cap. When fuel injection became a thing, I learned that stuff too. Give me a dwell tachometer and a timing light, and I could set the ignition timing, points dwell, and fuel mixture 'til the cows come home. Sometimes mechanical issues were puzzling, but things were a whole lot simpler to diagnose because even though engines today still require air, fuel, compression, and ignition to function, older engines had simple components and systems where each of these requirements was adjustable using relatively simple tools. My introduction to this mindset began when I was in the first grade in the 1960s. My dad was in the carport and he had the hood open on our '57 Mercury Monterey sedan. He had the intake manifold and the heads off the 312 V8, and was sitting on the ground removing the valves from heads and laying them out in order. I asked what he was doing and he explained the parts needed to be cleaned, and asked if I would like to help. I remember this like it was yesterday. Me, thinking: "get totally filthy and it'll be okay? Mom won't yell at me!" So following 30 seconds of instruction, I sat down where my dad had all 16 valves laid out on newspaper and scrubbed each one with a steel brush until they gleamed. After that experience, whenever I got in the car, it was a rush because I helped make it run. I was hooked. As the corpo-goobers say these days, I became "empowered with ownership in the process and invested in the continued success going forrrrwarrrrd..." By the early 1970s, emissions control measures and systems began to be added to vehicles. Next came electronic ignitions, closely followed by engine control units (computer or "brain") that modulated air, fuel, and ignition, followed by onboard diagnostics (OBD). If you owned a working garage and wanted to stay in business you needed to buy an engine analyzer that was about the size of a refirigerator and cost in the neighborhood of $20K. Ouch. Troubleshooting and diagnosing a problem is a skill that gets better with practice. The more you do it the better you get, and it's common when a popped error code (when the red engine light comes on) is not enough to help you figure out the problem. Yeah, it can point you to the most probable cause, and the cost of an ODB reader has come way way down (~$25 for a basic funtional one), but it's common to address one thing and BAM another error code pops. This is where the ability to troubleshoot comes in handy because chasing error codes can get frustrating. If you know how to relate one malunction to another, finding and fixing the problem becomes easier. The auto repair business, especially at a dealer's garage, is geared toward remove-and-replace (R&R) rather than troubleshoot and find out what the problem is. The reason for this is the billing structure; it's literally "by the book." This is probably why you had that experience with your vehicle, Tom B. The R&R process of problem solving is like throwing stuff at the wall to see what sticks. If this problem-solving sort of stuff is interesting to you, the Mustie1 channel above is really good because he's an old-hand, no-BS grease monkey. A fantastic channel that often mixes advanced automotive diagnostics with solid, old-school troubleshooting better than any others I've seen is South Main Auto. He's so good at it, local dealers bring him vehicles they give up on. And he finds the problem and fixes it. He even brings kids in to show them how to change a flat tire, change the oil, and other stuff everybody should at least understand, even if they don't do the job for themselves. The really cool thing is he talks the viewer through everything, including his thought process. This is gold because once you can think a certain way, troubleshooting becomes easier. South Main Auto: www.youtube.com/channel/UCtAGzm9e_liY7ko1PBhzTHA |
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Post by LTB on Jan 4, 2021 23:29:48 GMT -5
Like you Peegoo, tuning a 60's model car with Points, Condenser , distributer using Dwell meter and timing light and screw driver etc was pretty straight forward. They progressed to todays models and I can do somethings but some vehicles like my 2005 Ford Focus they stupidly tucked the Alternator between the engine and the firewall. You have to unbolt engine from the motor mounts and lift it up and forward to get to it. If the engine idles for extended period of time in hot summer the Alternator can and will go bad sitting in it for 30 minutes with A/C going in Hot Texas Summer is not a good thing. Also, Just to remove the thermostat you have to of course drain antifreeze fluid then remove the overflow tank (not a big deal) but then remove the Power Steering pump after removing all the belts (say whaaaatttttt?) and to put Freon in the A/C you have to remove cover under right front end of the car in front of the front wheel to access the valves? I think Ford tried their best to make it to where you would bring it in for repairs. Pleassssseeeee. One last thing, no replaceable Engine air filter. It is all one big sealed unit that you are supposed to replace in 100K miles for $300 just for the part. NOPE, won't be buying another one of these even if available. To be honest though it has been fairly reliable over the last 15 years. We just got my wife's Honda Accord paid off this month so we are going to put that amount of money and combine it with the House payment so it will be paid off in about 15 months instead of 3 years.
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MoJoe
Wholenote
Posts: 855
Formerly Known As: quiksilver
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Post by MoJoe on Jan 5, 2021 0:23:57 GMT -5
Here's a good one: timing belt skipped a few teeth on a camshaft. The reason is hilarious. Fate slipped that cam drive a mickey - ..sorry, couldn't resist. 🙂 @ 20:15: That one seems to be never getting old.. 😳 |
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Post by walshb 🦒 on Jan 5, 2021 8:30:13 GMT -5
Good story, Peegoo!
Also, in the video, I'm wondering how "the reason" got in there in the first place! And I was also surprised the guy was able to find it without removing half the engine parts.
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Post by ninworks on Jan 5, 2021 9:21:33 GMT -5
Diagnostics can be a real PITA. I have a 2010 Yukon Denali that had an intermittent parasitic draw on the battery. If it sat for a couple days without running the battery would drain to the point where I would have to either charge or jump it to get it started. Initially, every time I would check it for a draw the drain was within tolerance. 50mA is the max with the key off and I was only reading about 20mA. I finally decided to stand there and watch it while I had my amp meter hooked up in series with the negative battery cable to see if anything detrimental would happen. After about 10 minutes it hit with a 3.6 amp draw that would last for about 10 seconds, then it would drop to 220mA and stay there for 9 minutes, then drop down to the acceptable 20mA where it would stay for about 2 minutes before starting the process all over. I used a stopwatch to time the tests to see if it was random or not. I started with the fuse panel and removed one fuse then stood there and watched the meter until the drain cycle would restart. I'd replace that fuse and go to the next one. I repeated this same process for over 80 different fused circuits in the vehicle. It took me over 2 weeks of standing there waiting for the problem to appear. after going through all that and not finding the problem and since the timing on the system resetting was so consistent I figured that it had to be related to something with a microprocessor in it.
After I had gone through every fused circuit in the vehicle I crawled under the dash and pulled the Body Control Module out to where I could get to the 7 different multi-pinned connectors. I removed one and ran my 15 minute test. The problem was still there. I pulled the next connector leaving the previous one unplugged. The problem was still there. I kept removing connectors and running my tests until I got to the 6th connector on the unit. When I removed it the drain stopped. At that point I went to the dealer and they printed out the wiring diagram for everything that was connected to the offending connector. It showed the multiple fuses in the inside fuse panel that supplied power to numerous different wires in that connector. I plugged that connector back into the module then pulled all of the fuses that supplied power to the wires in that connection. The problem was gone so, I put one of the fuses back in and ran my 15 minute test. Still no problems. I kept plugging fuses back in and running my tests until the problem re-appeared. I figured out that it was the circuit that supplied power to the OnStar device. I removed the the wire from the multi-connector on the Body Control Module that went to the OnStar device and ran my test again. The problem was still there. So, it turns out that it was the Body Control Module itself. I had to have the dealer replace the module because the new one had to be programmed for my specific vehicle. After weeks of testing and lots of very VERY bad language I had to have them fix it anyway.
The moral of the story is that I knew EXACTLY what was wrong with it when I took it to them so all they did was put in and program the new module. The head mechanic, who printed out the wiring diagrams for me, was impressed that I was able to find the problem without the use of computer-based diagnostics. He also commented about the log file I had on my phone that I used to document the results of every single test I ran throughout the entire process. He was the one who was assigned the job when I took it in so they didn't gouge me on the cost. If they would have tried I would have gone ballistic on them after having gone through all the pains to diagnose the issue. It took me a couple months to find it but I did. I didn't work on it everyday but I'll bet I had at least 30 hours in the diagnosis.
I HATE electrical problems!!
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Post by Leftee on Jan 5, 2021 10:18:10 GMT -5
Parasitic load issues are the worst - in my book.
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Post by slacker 🐨 on Jan 5, 2021 10:36:02 GMT -5
Grab a beverage, kids. This is a protracted story. The electric window on my '04 Toy Tacoma truck's driver door started acting up a few weeks ago; it's the switch and motor that gets the most use. It would motor down just fine, but sometimes it would refuse to go back up. Sometimes it would go halfway and stop. Other times, no problem. I pulled the switch module out of the door and tested it, and the switches for all four windows were fine, along with the electric mirror controls and door lock switches. These switches carry higher current than what a meter uses, and that can mean a test like this not really reliable. An entire replacement module was $30 so I ordered one, it came in, and I swapped it in. All was good. A week later the window started getting balky again, so I ordered a new window regulator ($23) which contains a little motor on a mounting bracket, a sector gear, and a two steel roller tracks. I parked the truck in the driveway and popped the door panel off, got the old regulator out and the new regulator in. Since I was testing the new motor and switch module, the ignition key had to be in the run position so I left the key on as I worked. Everything was working well, so I began reattaching the inner door panel... I started smelling gasoline really strongly, so I peeked under the truck and there was a puddle of fuel on the driveway amidships, about two feet in diameter and more gas peeing out in a pretty happy little stream. GAH! I shut off the ignition and grabbed the fire bottle from the garage. With the ignition off, the leak turned to a drip and then stopped, which told me it was a pressurized line from the in-tank fuel pump. What the heck? I sopped up the fuel and rinsed everything down with soapy water before even thinking about moving the truck. While the driveway dried off I got the door reassembled. I crawled up under the truck (it's a Prerunner, plenty high to scoot under without ramps or jack stands) and I laid there in the fecal position looking around with a flashlight. Yeah, I know the term is "fetal," but the word I was thinking at the time made this the fecal position. Anyway, I found the problem: a short stiff rubber line about 16" long from the top of the fuel tank to a steel fuel line that runs forward to the fuel filter. It was leaking right through the rubber, in the middle of the tube. The connections were plastic quick releases, similar to a hydraulic line. I popped it off and got it to the shop to take a look under a bright light. The fuel line is a soft rubber jacket over a hard polyurethane tube, and it looked like sabotage because there was deliberate mechanical damage to the jacket; it looked like someone had taken an ice pick to it. Several random-looking little gashes in an area about the size of a nickel. I begin turning over in my head all the names of ex-GFs that maybe had some grudge, and it was three days before Christmas, so maybe one of them was thinking of me over the holidays... Hmmm. I sliced away the rubber jacket and there were matching gashes in the poly tube. I popped open the shop manual to get the name of the part, and as I walked to my car to zip over to the local Auto Zone, I saw a squirrel near another car on the street. TREE RATS! Bastages! It wasn't an ex. Squirrels have chewed the rubber hose on my gas grill more than once. The Auto Zone guy said it was a specialty part (no aftermarket), so I rolled down to the Toyota dealer and spoke with the parts guy. He looked it up and said, "whoa...that part is 85 dollars." He looked at me to see if I was going to walk. I quickly thought I could sleeve on some reg'ler ol' 3/8" rubber fuel line...but I held fast and said, "I'm already here...may as well go with it." He poked at the keyboard and said, "let's see if they still supply them. Okay, this shows there are 73 of them in the US right now." My blood pressure... He added, "and there are five on the local area. You can pick it up tomorrow after 10 am." As he entered my name and phone number for the order, he asked if I had all my Christmas shopping done. "I just finished it three seconds ago," I replied. When I picked up the part the first thing I did when I got home was wrap the replacement line with aluminum HVAC tape to discourage the tree rats next time they get up in there. With the part installed, everything works great and LUCKY ME I didn't have to drop the fuel tank to do it. I also replaced the fuel filter while I was under there and my hands were dirty. They say things happen in threes, so any bets on the last item that's gonna pop up? I don't even want to think about it. I had either tree rats or mice that chewed through the fuel line on my daughter's car. Was mowing the lawn near her car in the driveway when I got a strong smell of gasoline. Looked under her car and there's a decent sized puddle of gas. I made an appointment to have it repaired and, when I drove it down, it was really spewing gas with the engine running and the line pressurized. |
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Post by slacker 🐨 on Jan 5, 2021 10:49:28 GMT -5
Diagnostics can be a real PITA. I have a 2010 Yukon Denali that had an intermittent parasitic draw on the battery. If it sat for a couple days without running the battery would drain to the point where I would have to either charge or jump it to get it started. Initially, every time I would check it for a draw the drain was within tolerance. 50mA is the max with the key off and I was only reading about 20mA. I finally decided to stand there and watch it while I had my amp meter hooked up in series with the negative battery cable to see if anything detrimental would happen. After about 10 minutes it hit with a 3.6 amp draw that would last for about 10 seconds, then it would drop to 220mA and stay there for 9 minutes, then drop down to the acceptable 20mA where it would stay for about 2 minutes before starting the process all over. I used a stopwatch to time the tests to see if it was random or not. I started with the fuse panel and removed one fuse then stood there and watched the meter until the drain cycle would restart. I'd replace that fuse and go to the next one. I repeated this same process for over 80 different fused circuits in the vehicle. It took me over 2 weeks of standing there waiting for the problem to appear. Since the timing on the system resetting was so consistent I figured that it had to be related to something with a microprocessor in it. After I had gone through every fused circuit in the vehicle I crawled under the dash and pulled the Body Control Module out to where I could get to the 7 different multi-pinned connectors. I removed one and ran my 15 minute test. The problem was still there. I pulled the next connector leaving the previous one unplugged. The problem was still there. I kept removing connectors and running my tests until I got to the 6th connector on the unit. When I removed it the drain stopped. At that point I went to the dealer and they printed out the wiring diagram for everything that was connected to the offending connector. It showed the multiple fuses in the inside fuse panel that supplied power to numerous different wires in that connector. I plugged that connector back into the module then pulled all of the fuses that supplied power to the wires in that connection. The problem was gone so, I put one of the fuses back in and ran my 15 minute test. Still no problems. I kept plugging fuses back in and running my tests until the problem re-appeared. I figured out that it was the circuit that supplied power to the OnStar device. I removed the the wire from the multi-connector on the Body Control Module that went to the OnStar device and ran my test again. The problem was still there. So, it turns out that it was the Body Control Module itself. I had to have the dealer replace the module because the new one had to be programmed for my specific vehicle. After weeks of testing and lots of very VERY bad language I had to have them fix it anyway. The moral of the story is that I knew EXACTLY what was wrong with it when I took it to them so all they did was put in and program the new module. The head mechanic, who printed out the wiring diagrams for me, was impressed that I was able to find the problem without the use of computer-based diagnostics. He also commented about the log file I had on my phone that I used to document the results of every single test I ran throughout the entire process. He was the one who was assigned the job when I took it in so they didn't gouge me on the cost. If they would have tried I would have gone ballistic on them after having gone through all the pains to diagnose the issue. It took me a couple months to find it but I did. I didn't work on it everyday but I'll bet I had at least 30 hours in the diagnosis. I HATE electrical problems!! I had a car for my daughter (other one, not the same car as the fuel line issue) that would randomly have the battery go dead. Huge PITA. We were seeing an intermittent parsitic draw of several nearly half an amp. We went through the whole fuse pulling routine and it was ultimately traced to the cruise control system. I tried to fine a new stalk, but no joy, so we just pulled the fuse and ran with it that way. |
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Post by walshb 🦒 on Jan 5, 2021 11:33:49 GMT -5
Diagnostics can be a real PITA. I have a 2010 Yukon Denali that had an intermittent parasitic draw on the battery. If it sat for a couple days without running the battery would drain to the point where I would have to either charge or jump it to get it started. Initially, every time I would check it for a draw the drain was within tolerance. 50mA is the max with the key off and I was only reading about 20mA. I finally decided to stand there and watch it while I had my amp meter hooked up in series with the negative battery cable to see if anything detrimental would happen. After about 10 minutes it hit with a 3.6 amp draw that would last for about 10 seconds, then it would drop to 220mA and stay there for 9 minutes, then drop down to the acceptable 20mA where it would stay for about 2 minutes before starting the process all over. I used a stopwatch to time the tests to see if it was random or not. I started with the fuse panel and removed one fuse then stood there and watched the meter until the drain cycle would restart. I'd replace that fuse and go to the next one. I repeated this same process for over 80 different fused circuits in the vehicle. It took me over 2 weeks of standing there waiting for the problem to appear. after going through all that and not finding the problem and since the timing on the system resetting was so consistent I figured that it had to be related to something with a microprocessor in it. After I had gone through every fused circuit in the vehicle I crawled under the dash and pulled the Body Control Module out to where I could get to the 7 different multi-pinned connectors. I removed one and ran my 15 minute test. The problem was still there. I pulled the next connector leaving the previous one unplugged. The problem was still there. I kept removing connectors and running my tests until I got to the 6th connector on the unit. When I removed it the drain stopped. At that point I went to the dealer and they printed out the wiring diagram for everything that was connected to the offending connector. It showed the multiple fuses in the inside fuse panel that supplied power to numerous different wires in that connector. I plugged that connector back into the module then pulled all of the fuses that supplied power to the wires in that connection. The problem was gone so, I put one of the fuses back in and ran my 15 minute test. Still no problems. I kept plugging fuses back in and running my tests until the problem re-appeared. I figured out that it was the circuit that supplied power to the OnStar device. I removed the the wire from the multi-connector on the Body Control Module that went to the OnStar device and ran my test again. The problem was still there. So, it turns out that it was the Body Control Module itself. I had to have the dealer replace the module because the new one had to be programmed for my specific vehicle. After weeks of testing and lots of very VERY bad language I had to have them fix it anyway. The moral of the story is that I knew EXACTLY what was wrong with it when I took it to them so all they did was put in and program the new module. The head mechanic, who printed out the wiring diagrams for me, was impressed that I was able to find the problem without the use of computer-based diagnostics. He also commented about the log file I had on my phone that I used to document the results of every single test I ran throughout the entire process. He was the one who was assigned the job when I took it in so they didn't gouge me on the cost. If they would have tried I would have gone ballistic on them after having gone through all the pains to diagnose the issue. It took me a couple months to find it but I did. I didn't work on it everyday but I'll bet I had at least 30 hours in the diagnosis. I HATE electrical problems!! I'm impressed just reading this! Dang! They didn't try to hire you at the dealership!?  I had to perform a LOT of troubleshooting in my job in CNC Machines, but don't recall ever having to go through this much troubleshooting. Impressive! |
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Post by ninworks on Jan 5, 2021 14:33:24 GMT -5
Diagnostics can be a real PITA. I have a 2010 Yukon Denali that had an intermittent parasitic draw on the battery. If it sat for a couple days without running the battery would drain to the point where I would have to either charge or jump it to get it started. Initially, every time I would check it for a draw the drain was within tolerance. 50mA is the max with the key off and I was only reading about 20mA. I finally decided to stand there and watch it while I had my amp meter hooked up in series with the negative battery cable to see if anything detrimental would happen. After about 10 minutes it hit with a 3.6 amp draw that would last for about 10 seconds, then it would drop to 220mA and stay there for 9 minutes, then drop down to the acceptable 20mA where it would stay for about 2 minutes before starting the process all over. I used a stopwatch to time the tests to see if it was random or not. I started with the fuse panel and removed one fuse then stood there and watched the meter until the drain cycle would restart. I'd replace that fuse and go to the next one. I repeated this same process for over 80 different fused circuits in the vehicle. It took me over 2 weeks of standing there waiting for the problem to appear. after going through all that and not finding the problem and since the timing on the system resetting was so consistent I figured that it had to be related to something with a microprocessor in it. After I had gone through every fused circuit in the vehicle I crawled under the dash and pulled the Body Control Module out to where I could get to the 7 different multi-pinned connectors. I removed one and ran my 15 minute test. The problem was still there. I pulled the next connector leaving the previous one unplugged. The problem was still there. I kept removing connectors and running my tests until I got to the 6th connector on the unit. When I removed it the drain stopped. At that point I went to the dealer and they printed out the wiring diagram for everything that was connected to the offending connector. It showed the multiple fuses in the inside fuse panel that supplied power to numerous different wires in that connector. I plugged that connector back into the module then pulled all of the fuses that supplied power to the wires in that connection. The problem was gone so, I put one of the fuses back in and ran my 15 minute test. Still no problems. I kept plugging fuses back in and running my tests until the problem re-appeared. I figured out that it was the circuit that supplied power to the OnStar device. I removed the the wire from the multi-connector on the Body Control Module that went to the OnStar device and ran my test again. The problem was still there. So, it turns out that it was the Body Control Module itself. I had to have the dealer replace the module because the new one had to be programmed for my specific vehicle. After weeks of testing and lots of very VERY bad language I had to have them fix it anyway. The moral of the story is that I knew EXACTLY what was wrong with it when I took it to them so all they did was put in and program the new module. The head mechanic, who printed out the wiring diagrams for me, was impressed that I was able to find the problem without the use of computer-based diagnostics. He also commented about the log file I had on my phone that I used to document the results of every single test I ran throughout the entire process. He was the one who was assigned the job when I took it in so they didn't gouge me on the cost. If they would have tried I would have gone ballistic on them after having gone through all the pains to diagnose the issue. It took me a couple months to find it but I did. I didn't work on it everyday but I'll bet I had at least 30 hours in the diagnosis. I HATE electrical problems!! I'm impressed just reading this! Dang! They didn't try to hire you at the dealership!? I had to perform a LOT of troubleshooting in my job in CNC Machines, but don't recall ever having to go through this much troubleshooting. Impressive! I don't want a job. Especially at a dealership. I've been out of the loop for too long and I would be too slow to make any money. The dealers have a computer diagnostics program where they can hook up to the vehicle and it will tell them where the problem is so it doesn't take them as much time to find the problem as it did me. I just had to follow the logic and be methodical in my procedures. Since I had to spread out my testing over many different days it was paramount that I kept good notes so I could take up where I left off without having to backtrack or skipping over anything. I grew up in an automotive garage and did it professionally up until 1982 but that was long before all the computerized stuff was on vehicles. I did a lot of research online throughout the diagnostic process. That helped me figure out the chronological order of testing events when I found out what the primary importance of the components were. Pulling fuses is always where you start with a parasitic draw. After that I needed to figure out what the next most important doo dad was. I'm not going to lie to you. I was scratching my head a lot throughout the process. |
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Post by walshb 🦒 on Jan 5, 2021 16:48:22 GMT -5
I'm impressed just reading this! Dang! They didn't try to hire you at the dealership!? I had to perform a LOT of troubleshooting in my job in CNC Machines, but don't recall ever having to go through this much troubleshooting. Impressive! I don't want a job. Especially at a dealership. I've been out of the loop for too long and I would be too slow to make any money. The dealers have a computer diagnostics program where they can hook up to the vehicle and it will tell them where the problem is so it doesn't take them as much time to find the problem as it did me. I just had to follow the logic and be methodical in my procedures. Since I had to spread out my testing over many different days it was paramount that I kept good notes so I could take up where I left off without having to backtrack or skipping over anything. I grew up in an automotive garage and did it professionally up until 1982 but that was long before all the computerized stuff was on vehicles. I did a lot of research online throughout the diagnostic process. That helped me figure out the chronological order of testing events when I found out what the primary importance of the components were. Pulling fuses is always where you start with a parasitic draw. After that I needed to figure out what the next most important doo dad was. I'm not going to lie to you. I was scratching my head a lot throughout the process. Believe me, I know that feeling! And I don't blame you for not wanting a job at a dealership. But still, your troubleshooting techniques, and especially patience....just accept the compliment!  |
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Post by ninworks on Jan 5, 2021 17:06:14 GMT -5
 Thank you. I started out with the hopes that I could fix it myself. I just wasn't meant to be.
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Post by Peegoo 🏁 on Jan 5, 2021 18:16:17 GMT -5
Yikes! Driving a vehicle with a leaking fuel line is extremely hazardous. You, sir, are this month's winner of the Super Dave Osborne Award, given in recognition for commission of an insanely dangerous act that was only one qualifier away from winning the Darwin Award. Congratulations! SPEECH! SPEECH!  |
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Post by Seldom Seen on Jan 5, 2021 18:37:08 GMT -5
I'm leaving for Texas on Thursday and my F150 started making an intermittent but familiar noise today. It's either the early phase of an IWE problem or just cold/wet brake pads. Either way I think (hope) we make it through the trip without it becoming a big problem. Darn motor vehicles anyway!
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Post by Peegoo 🏁 on Jan 5, 2021 18:49:56 GMT -5
Check them tires, fluids, belts and hoses. When the red light pops on, it's usually too late to do anything about it.  |
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Post by Ricketi on Jan 5, 2021 19:17:01 GMT -5
I'm leaving for Texas on Thursday and my F150 started making an intermittent but familiar noise today. It's either the early phase of an IWE problem or just cold/wet brake pads. Either way I think (hope) we make it through the trip without it becoming a big problem. Darn motor vehicles anyway! I had that IWE problem with my 2018 F150 started at 400 miles on the odometer. The first time Ford replaced left IWE, Second time it happened they replaced left and right IWE. After that I looked into how the system worked and I thought the problem was somewhere in the vacuum system that operates them. I figured it was a check valve or a solenoid valve , relayed my thoughts to service manager. The left side made noise again so they replaced check valve. Good for 5 months and it happened again. They replaced IWE's and the solenoid valve. Ford wanted my left front drive shaft to study it. they replaced it with a new one. I got a extended warranty free from them for my hassle. It was problem free for a year after that and I traded it in for F250 , it made pulling my travel trailer easier especially in wind and traffic. Just a note: Vacuum keeps the IWE disengaged any drop of vacuum will try to engage IWE. |
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I had to perform a LOT of troubleshooting in my job in CNC Machines, but don't recall ever having to go through this much troubleshooting. Impressive!
Thank you. 
