Did you snug up those valley cover bolts while you were in there?
Electrical problems with 07 Yukon
- Thread starter schweg
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Ugh, no I didn't do that. I didn't see any oil leaks up there, so hopefully it's fine for now. Anyway, taking the intake manifold off turned out to be easier than I thought it would be. Only real problem was getting the fuel line disconnect to release. Had to buy three different tools before I found one that would work.
IMO that was the worst part was that ******* fuel line connector. I had 2 different tools I bought and they were both useless and I wound up using a pick tools to get it apart somehow.
Also there are 2 crossover steam pipes on in front and one in back that take little gaskets that usually come with the intake kit or the valley gasket kit I can't remember which one but it can't hurt to replace those too whenever you are in there or anybody else goes down this path. Also replaced the oil pressure sensor and the screen under it while I had access available.
thompsoj22
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while someone sits inside and holds the ign in the start "clicking position" tweak on the pos bat cable where the "wire" is crimped to the post adapter and see if there is any change. no starting amps and just voltage to light a few accessories, I would eliminate the positive battery connections before going to other possibilities. As long as the key was off when the battery drained the electronics should be fine.
I went ahead and replaced the positive battery cable yesterday and I went through every fuse. Didn't make a difference. The dash board still lights up, climate control system has power. No dome lights, no power in the doors. The headlights work but the high beams don't. No blinkers, fog lights, etc. Power seats work...
Finally wised up and called my buddy that has a tech 2 and we plugged it in last night. Looks like the ECU is fine. Couldn't establish a connection to the BCM. So it looks like that might be the issue. Would at least explain why random tings are still working. I'm looking for a cheap ~$70 used BCM right now to see if it fixes it. Not really sure what I need to look for in a replacement though. Here's a picture of the one I pulled out of the car. Is it important to match the P/N or do I just need to find one that came from a 2007 Yukon? Also does anyone know what the "BLUE" sticker means?
Still not giving up on the rat/squirrel theory, but so far I haven't found anything that looks chewed up.
Finally wised up and called my buddy that has a tech 2 and we plugged it in last night. Looks like the ECU is fine. Couldn't establish a connection to the BCM. So it looks like that might be the issue. Would at least explain why random tings are still working. I'm looking for a cheap ~$70 used BCM right now to see if it fixes it. Not really sure what I need to look for in a replacement though. Here's a picture of the one I pulled out of the car. Is it important to match the P/N or do I just need to find one that came from a 2007 Yukon? Also does anyone know what the "BLUE" sticker means?
Still not giving up on the rat/squirrel theory, but so far I haven't found anything that looks chewed up.
swathdiver
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When I saw all those codes, BCM was the first thing that came to mind, then the wiring from the tree rat. If the wiring is good, the BCM is the likely culprit. You need the exact part number that your vehicle originally came with and you need to sign up for a subscription over at ACDelco TDS so your buddy can use his Tech-2 to program the BCM to your vehicle. This way all of your options work besides setting the VIN to the computer.
If you clear codes and then get the new ones now that power has been restored, this will help narrow down where the fault lay. I didn't read them all. AllDataDIY will list every code and then you can run the troubleshooter on each one, they should all point to a bad BCM but if they go off in another direction, by all means follow the trail just to be sure.
Joseph Garcia
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If you confirm that the BCM is the source of your issue, then you can order a replacement at Rock Auto. I replaced mine in August, and I was able to reprogram it to my truck using my Tech 2 and the sage advice and guidance from @swathdiver .
The cost from Rock Auto was $172.79, plus a $25 core charge, which was refunded, upon my returning the old BCM to them.
The cost from Rock Auto was $172.79, plus a $25 core charge, which was refunded, upon my returning the old BCM to them.
Success! I went ahead and replaced the BCM this evening and it started right up. Everything seems to be working fine now (engine cranks over and starts, dome lights, radio, door locks, ect).
I decided to buy a used BCM that was programmed for my VIN instead of trying to program it myself with the tech 2. For no good reason, I bought it from Deering's Sales in MN (320) 403-4000. They answered all my questions over the phone and sent me a programmed BCM with matching P/N within a week. It cost $195 including the programming and shipping. You could probably get one for ~$70 on ebay, but you would have to program it, etc. and I was getting tired of having to borrow my son's car. Case closed.
I decided to buy a used BCM that was programmed for my VIN instead of trying to program it myself with the tech 2. For no good reason, I bought it from Deering's Sales in MN (320) 403-4000. They answered all my questions over the phone and sent me a programmed BCM with matching P/N within a week. It cost $195 including the programming and shipping. You could probably get one for ~$70 on ebay, but you would have to program it, etc. and I was getting tired of having to borrow my son's car. Case closed.
thompsoj22
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i learned how significant the BCM truly is by watching this thread. Your description of "clicking" from the starter solenoid but not turning over had me convinced it was a simple power/connection to starter issue, maybe even an ignition switch? I couldent have been more wrong, I have a tech2 and threads like this "school me" that vehicles have changed so much, Allways diagnose with test equipment and leave the guessing to those fortunate enough to be troubleshooting a 1967 volkswagon beetle!
iamdub
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Low power, especially a slowly dying battery, does more harm to these things than no power. If it's gonna sit, either keep in on a trickle charger or disconnect the battery altogether.
