I have a 2013 2.5L Chevy Malibu LS, which had a bad ECM (Water got in and destroyed part of the board causing random sensor errors and randomly killing the car when driving, randomly deciding not to start, and causing the rpm tachometer to cease to work unless car was restarted). I ordered a new ECM for the exact model of my car, same part number and they programmed the VIN correctly however despite it being installed correctly the car refuses to crank and start, no security, no other lights beside check engine light, the only code that comes up is a check engine light code for Crankshaft Position Relearn which in normal considering it's a new ECM. I'm stumped at why the car has a NO START condition. Anyone have any ideas? I confirmed it had to be the new ECM causing this issue as I reinstalled the old ECM and it started up like it did before.
Your immobilizer is active.
After flashing the replacement ECU with proper VIN and calibrations you need to also program the immobilizer to store the sync codes in the replacement ECU. It needs to be done while connected with your immobilizer module and key so can not be done remotely like your supplier did for flashing the VIN and calibrations.
Turn your key to "ON" position and look at your instrument cluster, You will see a padlock symbol lit solid.
Are you located in US or elsewhere? In the US there is a manual procedure you can do. Elsewhere then you must use a good diag tool.
The dash going out during crank is pretty common on GM, I would only investigate further if you still have trouble after programming immobilizer.
Programming (US ONLY)
- Set up a battery maintainer on car.
- Insert key and turn ignition to "ON" (do not crank") leave there for 10 minutes. (not a second less)
- Turn key off then back to "ON" (do not crank) and leave there for another 10 minutes.(not a second less)
- Turn key off then back to "ON" (do not crank) and leave there for a final 10 minutes.(not a second less)
- Turn key off and wait 10 seconds. DONE.
Normally the security light is solid during the 10 minutes and when you see it go out then its ready for next step. If the light never turns off just switch after 10 minutes but usually this means something is wrong.
So after some research I've discovered these Chevy Malibu ECMs have a part number, a service number, and a hardware code. The hardware code is identical to the part/service number and may appear to be the correct ECM but is heavily different. It's the middle 8 numbers at the top and needs to be exactly the same as your new ECM. Also there is a 4 letter code at the top right that also needs to be the exact same for example my old ECM was ABMX but my new ECM was ABVT. When ordering a new ECM make sure ALL numbers match and check everything 4 times and have someone with a fresh pair of eyes check. Also always do proper research for your brand of ECMs.
Also as a side note for anyone who has a similar problem: The car has a VATS immobilizer system and does not need to be reprogrammed to the new ECM. As long as your new ECM is properly VIN programmed by the company your ordering it from or a dealership it should just work because of how a VATS immobilizer system works compared to a PASSKEY/PASSLOCK System.