PCM Ground Circuits and Locations Wanted

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Alberta Tahoe

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Where is the best resource to find all of the locations for the grounding circuits for the PCM?
I've checked the usual website and online sources however most seem available by subscription. Anyone have any links? Maybe there's a specific OEM manual other than buying the entire set of books?
I'm troubleshooting a no start condition (it goes far beyond that actually and I have a couple of threads dedicated to the problem) and am fairly certain it has to do with a poor ground from the PCM to the chassis. I've found a few already just by nosing around but from what I can tell, there might be a dozen locations to investigate.
Any help is greatly appreciated.
 
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Alberta Tahoe

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Nothing?
Am I limited to Auto Zone and their collection of schematics?
If I have to take out a subscription to get decent drawings, does anyone have a recommendation?
 
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Alberta Tahoe

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That's not the first time someone has mentioned them.
I ordered a complete service manual and depending on how thorough it is, I may have to make a visit to the alldata website.
Thanks for that.
 

RET423

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I had to remove and reinstall a 5.3 last month in a 2006 Yukon XL (replaced the front section of the GMT 800 Frame), when I got ready to fire it up it spun well but would not start; I suspected that we missed a ground somewhere.

That was in fact the issue, we had both bellhousing to cab/firewall grounds reconnected but had missed the ground that shares the same bolt on the block with the negative battery cable (drivers side, low and forward on the block), the smaller ground wire had been pulled up out of view when I put the negative cable back on.

I put that ground back on and the engine fired up as if it had been running all day, the only other ground that I remember beyond those 3 is a bellhousing to the front drivers side cab mount pedestal, also my 2004 Tahoe only has one of the bellhousing to cab/firewall grounds.
 
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Alberta Tahoe

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....I suspected that we missed a ground somewhere.
... had missed the ground that shares the same bolt on the block with the negative battery cable (drivers side, low and forward on the block)...the only other ground that I remember beyond those 3 is a bellhousing to the front drivers side cab mount pedestal, also my 2004 Tahoe only has one of the bellhousing to cab/firewall grounds.

Thanks for that. Something I'll be sure to investigate.
As a follow-up, I purchased a complete service manual from:

https://www.ebay.com/itm/Chevrolet-...2000-2006-Service-Repair-Manual-/262735761691

Plenty of schematics in there although I've yet to go through it thoroughly.
I also picked up a Tech 2 scanner from:

https://www.aliexpress.com/store/pr...&terminal_id=c7a3c585127d4e68b57381f9471e0dfd

Still waiting on the scanner.
AND, I bought another Tahoe. This one runs and is a 2003 model.
I should be good to go for while now.
 

RET423

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Thanks for the link, I just ordered one of those manuals myself :)

I also have had the knock-off Tech-2 for a couple years, it works very well
 
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Alberta Tahoe

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Excellent.

I also have had the knock-off Tech-2 for a couple years, it works very well

I'm hoping I can use it to diagnose the dead 2006. I have my doubts. At the very least, it will help to keep on top of the newest addition.
 
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