Hi everyone,

I have a 2023 Cadillac Escalade bought at a US auction as stolen/salvage title and imported to Europe.

The car won’t start and is showing DTC B1977 (Telematics Requested Immobilization). OnStar module is fully bypassed and physically removed. The code now appears only in the BCM.

Questions:

• Does anyone have a working solution for this problem?

• Will replacing the BCM with a new one fix it?

Any advice or experience would be greatly appreciated.

Thanks!

Hi,
Yes replacing BCM with a new one would work, had the same thing with Cadillac Lyriq - car stolen, Telematics imobilized the vehichle. Had to replace BCM, redo the Immo in order for the car to start again.

Global A module it was possible to remove theft flag from BCM by editing epprom, there new global B modules have encrypted MCU so as far as i researched - no solution yet.
If you want to have the car fully functional you will need new TCU too, cause lots of a systems in the car are going trough Telematic module on these new cars.

@nev3r Hi,

thanks a lot for the detailed reply and for sharing your experience with the Cadillac Lyriq – really helpful.

I’m planning to order a new BCM + new TCU and have them programmed (VIN match + immo relearn). My main worry is: if the vehicle is still listed as “stolen” in the GM/OnStar database, could the new modules still receive the disable command again?

In your Lyriq case – did you have to contact GM/OnStar first to clear the stolen flag on their server side before or after swapping the modules? Or did it stay unlocked just by replacing the hardware?

Any advice on this would be greatly appreciated. Thanks in advance!

16 hours ago, alywow said:

@nev3r Hi,

thanks a lot for the detailed reply and for sharing your experience with the Cadillac Lyriq – really helpful.

I’m planning to order a new BCM + new TCU and have them programmed (VIN match + immo relearn). My main worry is: if the vehicle is still listed as “stolen” in the GM/OnStar database, could the new modules still receive the disable command again?

In your Lyriq case – did you have to contact GM/OnStar first to clear the stolen flag on their server side before or after swapping the modules? Or did it stay unlocked just by replacing the hardware?

Any advice on this would be greatly appreciated. Thanks in advance!

As far as I'm aware Onstar does not have service in Europe, so probably no way of relocking the car again. And you do change TCU - its has different IMEI which are not in the database.
I tried contacting Onstar in the first place before changing the modules, but that was just waste of time, they just push you arround from one rep to another, in the end nobody knows what to tell you- and the fact that the car is outside of USA does not help either.

Another thing- theft lock was sent to the car due reporting it to be stolen- it might be already removed from the stolen database, due to fact it was recovered and sold by the auction- but since it has no service in Europe- BCM is still keeping the Theft lock flag until TCU doesn't instruct him differently.

For the Lyriq- new BCM and TCU , car is unlocked- driveable with no future issues.

Hello, were you able to find a solution? I have the same issue got a new bcm but can’t get a new telematic on a Cadillac Escalade 2026 as it is back order have to wait two Months. If I installed new bcm and unplug the telematic will the car start?

Thank you

This all being Global B. What surprises me is how the start thread shows only a few modules have lost or show NO communication. The 23 Envision I have was in an accident ....drained the battery completely dead. Battery was replaced and minor wirings for headlights and short range radar sensors were repaired. However the radio hvac , and cluster do not turn on at all. I will have to get a print out, yet I am told 7 modules show NO comms . Local independent shop here in the states mentioned it was towed wrong (key not in the vehicle) and possibly went into theft mode....... Vehicle will start / drive , yet no cluster, radio, hvac controls, what gives.

All these units are on SWCAN bus. Sounds like you have issues with that, rather than active theft lock.