changed ecm, now wont start! HELP!!

[hasher]

i just joined this forum for some help(sounds like smart people on here)!
we are just a small repair shop and not to familular with the chev duramax.
we had a guy towed in with an 05 chev 2500 crewcab, 6.6 lly ,auto.
the ecm and other parts under the front right of the pickup were smashed. we replaced all the parts and the ecm from another 05 chev 6.6l, but now the truck cranks over but will not start. the security light on the dash flashes. i was told to change the big black box that is under the steering colum(elec chas cntrl mod) with one from the same truck the ecm came from (wrecking yard), so we did. and still wont fire!
can u guys help?
we dont have a local gm dealer. (in the boonies, Canada)
how do we get it to re learn the ecm?
please use lamans terms and spasifics please:grin:
thanks
greg
gt auto

[Tordne]

It is more than likely the VATS security system killing the vehicle because it is not paired/linked with the Body Control Module (BCM). This is to be expected when changing out an ECM.

Typically a dealer would use the GM TechII tool to resolve the issue, our EFILive customers would use the EFILive software and FlashScan interface to relink the PCM and BCM controllers, or disable (turn off in the calibration) the VATS security linkage.

Without any tools I'm not sure how you might get around that problem. Might pay to call Guy from SoCal Diesel or one of the other diesel specialists in the USA. They are listed on our resellers page here: http://www.efilive.com/index.php?option=com_content&view=category&layout=blog&id=38&Itemid=94

Cheers,

[killerbee]

Greg, there is a 30 minute relearn procedure before the new ECM will take. Also, you may still have a problem, because your new ECM may not be coded with the correct OS.

[killerbee]

Based on some recent observation, I wonder if there is a sep table for idle pulse width. There is as much as a 250 us (pulse low to high) pulse difference at idle, which may lead to some rough idle for many tunes.

Just some thoughts.

[hasher]

we did the 30min relearn and now it starts. it will make the treck to the dealer for final scan once its finished.
thanks guys
greg