l_kusler

So my pcm is gone, tried several different attacks at it and no response.

I have a used pcm from a '03 6.0 2500 from a wrecker that i dropped in. Obviously the vin doesn't match my 03' 1500. It cranks fires right up and immediately drops the fuel after a half second. VTD. anti-theft relearn doesn't bypass this of course either. i don't expect this, and know i need a retune anyway.. So a couple questions. Whats the easiest way to go about this? I have hp tuners at my disposal. Should i go to the dealership and have a complete reflash done to the pcm so the vin is correct and it doesn't need a segment replacement for the 60e from an 80e, then go about tuning it with hp normally? Can the dealer reflash to a stock tune with just a pcm in hand or do they need the truck?

white lightning SS

iTrader: (3)

The dealer needs the whole truck. Mail order guys can go without. What is the part number on the PCM from your truck. I may have one for you. If the number of the one you put in does not match it probably wont work.

l_kusler

i have service number 12582605.. seems to be rare number that was updated..
The wrecker unit is 12576106 According to gmhightech this is an interchangeable pcm between vehicles from 03 to 07 as long as it is completely reflashed.

http://www.gmhightechperformance.com...ms/page_3.html

The part numbers are listed the same in alldata for both trucks for replacement. 8901773- the newest sub up. With the wrecker pcm installed, it communicates with bcm, attempts to run the engine and leaves no codes aside from anti-theft. So i think i'm only being held back by the mismatched vins shutting down the fuel, and of course the tranny being an 80, so i should be good to go after the baseline os tune has been flashed? Yea, unfortunately no one has an offboard tool around these parts so the truck will have to be towed in to the dealer. Let me know if you know otherwise on this so i can save the tow bill for now, but thats what i'm planning for possibly tomorrow... thanks for your help

GMCtrk

iTrader: (27)

did you try the relearn process...i.e. start it, it shuts off, leave key in on position for 10 minutes, then turn off for 30secs, then repeat 3 times?

l_kusler

yea, i did similar.. I swapped the pcm in, turned to run. security light was on, left for about 11mins, cycled off for 10-15secs, then repeated 2 more times. still does the instant shut off. Security light comes on to let you know it works on key cycle now then goes out. Yet everytime i attempt to start it sets the theft code. I will try this again tomorrow, just to make sure, but I still think this has something to do with mismatched vins. Unless someone has swapped pcms and been successful before without retune?!

white lightning SS

iTrader: (3)

You need to match the vins for the Passlock relearn to work. The dealer will hook you up. Dont let them charge you more than 1 hour labor.

l_kusler

Well guys, thanks so much for all the help. She's up and running.

But... I have a story to learn from.
My handheld is the culprit behind all my pcm headaches. I learned this the hardest way. I went to install a tune with the supplied diablo predator and on install it crashes/shorts the pcm. This is what originally happened without me catching on; being a fresh motor drop in and the handheld working fine before, i thought i had some wiring issues etc.. I paid the price and made another pcm a fuse to find this out. Stupid.. absolutely stupid.. At least i know now that it was not something else in the truck. And at least i got the pcms for under a $100, no doubt, but still some major frustration here. So my predator is being used as a clay pigeon as we speak.

Anyways, thanks again fellas