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A "how to" for removing the ECM/TCM

84K views 64 replies 26 participants last post by  Ntrain2k 
#1 ·
So I started to take out the PCM and TCM from my SS today and it was so easy that after I had them both out in about 2 minutes I thought to myself...I should have taken pictures. So here are some pics of the units, wire harnesses, and location. :crazy:

This first pic is of the cover that is easily removed by two release tabs.




This pic shows you the holder and the wiring harnesses that are easily unplugged. I found it easier to pop out the PCM first and slide it up out of the holder and lay it flat on it's back so I could see how the wiring plugs release. There is a release tab and then a grey bar that you pull forward. Very Easy :thumbsup:




This is a pic of the actual units :) Very clean and new :thumbsup:



Cheers!! I hope this helps!!
 
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#3 ·
Great Pictures

Some additional useful info:
Once the cover is removed, the modules are held into the support bracket by arns at the top of the modules made into the support backet. Pull the end of the arms up, tilt the top of module away from the bracket, then lift the module up and out of the bracket. Wire harness/connector still attached to modules.

There are three connectors on the ECM and one on the TCM. As described in a previous post the connector is tight. Rock it up and down while pulling and it will come off. Of course after releasing the connector clamp.

Also got the following price on the ECM and TCM from a local GM dealer:
ECM (12596679) - $262.72
TCM (24234503) - $85.33
 
#4 ·
c72lt1

I'm not sure that's the correct ECM for the TBSS. I just picked up a new ECM and TCM for a TBSS from my local dealership today. The ECM part number is 12597883. And it lists at $437.86. My cost was $306.50. Your TCM part number is correct, 24234503. It lists at $124.75, but my cost was $93.56.
 
#10 ·
As promised Vector tuned my parts same day and shipped them back to me overnight :) IT took all of about 5 minutes to plug the harnesses back in and snap the ECM/TCM back into place :yes:

Let the FUN BEGIN!!!:thumbsup:
 
#28 ·
Since you took the time to create this thread and take pictures, the least I could do is say, Thank you very much! :yes:

I was putting off a VM tune simply because I was nervous about removing the ECM/TCM. Your instruction and pictures made all the difference. Like you said, its a simple 3-5 minute job, when you know what to do.

Your taking the time to help other SS owners is what good forums like this one is all about! :thumbsup:

Thanks again.
 
#16 ·
crank relearn and having 2nd set of ECM & TCM

I've been reading this thread and other related threads about why people are buying another ECM & TCM. Please correct me if I'm wrong in this conclusion:
If you need zero days down you have to buy the ECM & TCM, ship those to Vector, and when it comes back, drive to the local dealership and do a crank relearn on your flashed ECM & TCM. Once that's done, you now have the original ECM & TCM that are virgin stock, and the new set that is programmed. If you have to update the programming, you pop out the mod set and pop back in the stock set.

So, for the purpose of not having a couple days down, you're paying $400+ for the ECM & TCM plus the cost of the crank relearn -- free to $50 or so.
Correct? Seems like a high cost for having 2 days down. Could rent a car for $30 a day for much less (or drive your other car if you have one)
Thanks
Roy
 
#17 ·
luvchampagne said:
I've been reading this thread and other related threads about why people are buying another ECM & TCM. Please correct me if I'm wrong in this conclusion:
If you need zero days down you have to buy the ECM & TCM, ship those to Vector, and when it comes back, drive to the local dealership and do a crank relearn on your flashed ECM & TCM. Once that's done, you now have the original ECM & TCM that are virgin stock, and the new set that is programmed. If you have to update the programming, you pop out the mod set and pop back in the stock set.

So, for the purpose of not having a couple days down, you're paying $400+ for the ECM & TCM plus the cost of the crank relearn -- free to $50 or so.
Correct? Seems like a high cost for having 2 days down. Could rent a car for $30 a day for much less (or drive your other car if you have one)
Thanks
Roy
Not that I have there specific tunes or anything, but I have a Westers tune for the I6. The reason I paid extra to keep the factory computer was for towing. The performance tune I got reduces my towing ability. I tow a couple times a year, so it made sense to keep the factory computer for those occassions.:cool:
 
#20 ·
TMONEY-2125 said:
Ummmm Guys can someone translate for us new to mods what is this ya;ll are taking aboue and what does it do?
Tune= a retune of your factory computer. Changing the settings to optimize performance or gas mileage or towing. Many things can be done.

Yank SS3600= a performans torque converter that changes the stall speed. Its all about what kind of performance you want to get out of your truck.:cool:
 
#25 ·
Gonna bring this thread back from the dead....

To the guys that have gotten a spare set for services runs to the dealer...what did you tell them when you needed a crank relearn? I'm thinking they are going to be like....."why do you need a crank relearn, it's a new truck..."?

Also, I just want to make sure that the mileage is not stored on the ecm or tcm.
 
#26 ·
I took the dumba** approach at the dealer....I called OnStar, told the operator "hey, I got a check engine light glowing on my dash...what's that mean?" OnStar did a remote vehicle diagnostic, told me what it was (crank variation problem) and the code number: PO315.

Then I got OnStar to direct me to the nearest Chevy dealer, pulled in there, and told the service manager "hey, OnStar told me to get to a dealer quickly...I've got a PO315 error code!".

The service writer looked it up, grabbed his scanner and hooked it up to the underdash plug, followed the scanner prompts, and the light went out.

Took all of 15 minutes...asked what I owed, he said, "forget it". Gave him $20 for lunch, and was on my way.

I got the guy's name before I left, and sent a glowing thanks to GM about this guy via their customer service website. That must have been a good idea, because the service writer sent ME a thanks e-mail a couple of days later.
 
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