PCM Swap and Compatability

[Alberta Tahoe]

What is the criteria for swapping a PCM from one vehicle to the next?
Example: My 2006 Tahoe is dead in the water. I have an opportunity to purchase a running 2003 Tahoe for very few dollars. In an effort to find the solution to the 2006's no start issue, can the PCM from the 2003 be transplanted into the 2006?
I'm at the point in the diagnosis and repair where replacing suspect components is all about that I can do.
I've more than one thread here looking for possible solutions however everything tried up to this point has not corrected the problem.

 

[6speedblazer]

cant be swapped without some work.

2003 and 2006 should both be a P59 ecm and they might have the same operating system. But the truck wont start and stay running without out disabling vats at the very least. If you know anyone with HPtuners or efi live they could disable vats on the 03 pcm and trying it on the 06.

what issue are you having that you suspect is the ECM?

 

[01ssreda4]

As long are both are DBW throttle bodies it should be almost an identical swap other then the vats as mentioned.

 

[Alberta Tahoe]

what issue are you having that you suspect is the ECM?

http://www.tahoeyukonforum.com/threads/intense-electrical-issue.92892/

http://www.tahoeyukonforum.com/threads/electrical-issue-is-expanding.93566/

 

[Alberta Tahoe]

As for the disabling the VATS, I can probably find somebody locally to do it. Being an old carburetor guy, I haven't had any need for tuning software...until now.

Can't say if it's the PCM or something more basic like a corroded connector buried somewhere that I haven't uncovered yet. I've given it a fairly thorough going over but there are still a few things left I can try before I get into parts swapping (which is contrary to my earliest automotive training).

 

[retiredsparky]

Before you start buying parts vehicles, or replacing ECM's, pull the fuse block assembly under the hood and look at the bottom side for any signs of corrosion. If fuse holders get overloaded or stressed, heat can cause loose connections.

GM believes in providing a convenient hole on the engine side of that fuse block that mice seem to find attractive. They will often sit under the fuse cover and eat seeds and do other things that can cause corrosion over time. Tape a small piece of metal or a fender washer over the hole (it is about 3/4" X 1"). I have seen mouse signs in multiple fuse blocks over the years.

If you live where road salt is common, remove all ground connections, sand the surface, use a serrated washer for the smaller connections and a little bearing grease or anti-oxidant on the connection.

Could you have corrosion inside a power or ground lug? Sometimes that corrosion isn't visible. New battery cables are cheaper than ECM's. Keep us posted.

Larry

 

[Alberta Tahoe]

I've gone over most of the power cabling (including grounds) although your idea of lifting the fuse block certainly warrants some attention. I've not found anything to this point although from the symptoms (such as the impression of all power being momentarily disconnected while driving) it seems to me it is probably something as simple as a corroded terminal somewhere. I had hoped that the ignition switch might be the culprit but that wasn't the case. That was only 40 bucks though.
I hadn't actually planned to start swapping out parts yet. I'm just familiarizing myself with what might be involved such as having the VATS disabled should I decide to exchange the PCM. Rather than a replacement, I'm inclined to disconnect it completely and examine those terminals.
I'll be back at it next week.