Rampant Electrical Gremlins - Need Harnesses?

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Rocket Man

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Figured I'd post an update on this in case anyone is similarly struggling. It turned out it was, in fact, the ECU going out... at least for the knock sensor issue. $800 because I had to have a shop do it (guess you have to have a special reflashing tool?), but that problem has been no more ever since.

Still got all kinds of BCM issues, BUT I actually think I've narrowed that down to the stupidest thing I could think of. The driver's side window switch panel. If I tear it apart and clean up the board-to-board connector contacts all my gremlins go away for about 1-1.5 weeks. That ain't just a switch panel, it's a little mini computer. I haven't been able to justify the $200 for a replacement yet, but I'm confident that's the source of the body gremlins now.
It won’t just cost you the $200 for the driver switch module- it needs to be programmed to hour vehicle also. Just the cost of programming these 2 modules would have paid for a Tech2. You might still seriously consider buying one, they pay for themselves in no time. It’s really the only good way to work on our electrical systems.
 
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Kwing

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It won’t just cost you the $200 for the driver switch module- it needs to be programmed to hour vehicle also. Just the cost of programming these 2 modules would have paid for a Tech2. You might still seriously consider buying one, they pay for themselves in no time. It’s really the only good way to work on our electrical systems.

Barf. I mean I REALLY appreciate the heads up cuz I would have been PO'ed if I bought it THEN figured that out, but still barf.

I guess it's just that time to bite the bullet on a tech 2. Hopefully they've come down in price since I last looked 6 years ago, but I won't get my hopes up...

Thank you!
 

Rocket Man

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Barf. I mean I REALLY appreciate the heads up cuz I would have been PO'ed if I bought it THEN figured that out, but still barf.

I guess it's just that time to bite the bullet on a tech 2. Hopefully they've come down in price since I last looked 6 years ago, but I won't get my hopes up...

Thank you!
They’re around $300. You can check chinacardiags on eBay but I would look for one from a us seller thst has units here so you don’t have to wait forever for China shipping. That’s what I did, got one for about the same price.
 
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Well that ain't bad at all. I seem to remember a 4-digit price tag. $300 I can handle.

Thank you again! :)
 
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Kwing

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Re-read some of the reply's , it's very good advise.

Oh I did, and they were fantastic suggestions. I guess I should give a more thorough update...

The truck was due for emissions testing in August. It couldn't pass with the knock sensor. So I went elbow deep and tore the entire harness and ECU out.

Inspected every square inch and found nothing. For good measure, I cut off all the jackets and traced/replaced the knock sensor wires from the ECU to the sensor and put ANOTHER pigtail connector on for the sensor. Cut off and replaced all the ground ends and replaced all 3 battery cables.

Put it back together and got the ol' MIL middle finger.

Emissions were due in 2 weeks and I was desperately trying to survive online schooling with a kindergartener at this point. Out of time and out of patience, I took it in. They diagnosed the ECU in 20 minutes, presumably using the tech 2 (remember, last I looked I remember them being quite pricey).

The guy fully expected me to do the job myself. I don't trust shops. Every shop I've been to in 22 years of owning cars has screwed me. Usually either break more than they fix or charge me for repairs that don't solve it, then charge me again for the right repair. This guy knows this. I have a "relationship" of sorts with him because he's the only shop my elderly mother can go to and come out in one piece... and I audit their work every time :). So he told me it was the ECU and and said I could come get it, he then told me it had to be flashed after the swap I threw up my hands and paid him to do it.

So I DID follow the advice, it just wasn't enough this time... now that I know the tech II isn't over a grand, next time I'll take a wack.

I own all GM's and that ain't changin' any time soon...
 

Tonyrodz

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Oh I did, and they were fantastic suggestions. I guess I should give a more thorough update...

The truck was due for emissions testing in August. It couldn't pass with the knock sensor. So I went elbow deep and tore the entire harness and ECU out.

Inspected every square inch and found nothing. For good measure, I cut off all the jackets and traced/replaced the knock sensor wires from the ECU to the sensor and put ANOTHER pigtail connector on for the sensor. Cut off and replaced all the ground ends and replaced all 3 battery cables.

Put it back together and got the ol' MIL middle finger.

Emissions were due in 2 weeks and I was desperately trying to survive online schooling with a kindergartener at this point. Out of time and out of patience, I took it in. They diagnosed the ECU in 20 minutes, presumably using the tech 2 (remember, last I looked I remember them being quite pricey).

The guy fully expected me to do the job myself. I don't trust shops. Every shop I've been to in 22 years of owning cars has screwed me. Usually either break more than they fix or charge me for repairs that don't solve it, then charge me again for the right repair. This guy knows this. I have a "relationship" of sorts with him because he's the only shop my elderly mother can go to and come out in one piece... and I audit their work every time :). So he told me it was the ECU and and said I could come get it, he then told me it had to be flashed after the swap I threw up my hands and paid him to do it.

So I DID follow the advice, it just wasn't enough this time... now that I know the tech II isn't over a grand, next time I'll take a wack.

I own all GM's and that ain't changin' any time soon...
I paid $200 to get my van's pcm flashed when it went bad. If he charged you $700 to flash yours.....
 
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Kwing

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I paid $200 to get my van's pcm flashed when it went bad. If he charged you $700 to flash yours.....

No, no. He charged $160 or $170 to flash it. The rest was the ECU and labor to install it. I remember pricing the ECU, evaluating the effort, and thinking he did me right. It was frustrating that I couldn't do it, but he was fair.
 

Tonyrodz

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No, no. He charged $160 or $170 to flash it. The rest was the ECU and labor to install it. I remember pricing the ECU, evaluating the effort, and thinking he did me right. It was frustrating that I couldn't do it, but he was fair.
My misunderstanding.
 

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