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john -aka eauto
john -aka eauto, The Car Guy
Category: Cadillac
Satisfied Customers: 16286
Experience:  15 years as a auto tech
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1999 Cadillac Escalade: car wont start due to the anti-theft system

Customer Question


I took my 1999 Cadillac Escalade into the shop. I pulled it around, but they used the wrong key to try and get it started yesterday and now the car won't start due to the anti-theft system. We let it sit overnight and it still won't start. Any ideas?
Submitted: 8 years ago.
Category: Cadillac
Expert:  john -aka eauto replied 8 years ago.

Ok its stuck in security mode

OK, there may be an issue with the security system, but lets try a relearn procedure. It is posted below. Try it an let me know what happens.

30-Minute Relearn Procedure



Use this procedure after replacing any of the following components:

The PASS-Key III plus keys
The theft deterrent module (TDM)
The powertrain control module (PCM)


This procedure is not available on vehicles equipped with EXPORT configured TDMs.
When performing the 30-minute relearn procedure, all previously learned keys will be erased from the TDM memory. Additional keys may be learned after performing the relearn procedure.
When replacing a TDM with a GM SPO Replacement Part, ensure the procedure to setup a new TDM is performed prior to the 30-Minute Relearn Procedure.
  1. With a master vehicle key, turn ON the ignition, with the engine OFF.
  2. Observe the security indicator. After approximately 10 minutes, the telltale will turn OFF.
  3. Turn OFF the ignition, and wait 5 seconds.
  4. Repeat steps 1-3 two more times for a total of 3 cycles or 30 minutes.

    Important: The vehicle learns the key transponder information and/or passwords on the ignition switch transition from OFF to RUN. You must turn the ignition OFF before attempting to start the vehicle.

  5. With a master vehicle key, start the vehicle. The vehicle has now learned the key transponder information and/or the ECM has now learned the fuel continue password.
  6. If additional keys are required to be learned, continue to step 7.
  7. With a previously learned master key, turn ON the ignition, with the engine OFF.
  8. Turn OFF the ignition and remove the key.
  9. Within 10 seconds insert the key to be learned. Turn ON the ignition with the engine OFF. The vehicle has now learned the new key.



john -aka eauto and 3 other Cadillac Specialists are ready to help you
Customer: replied 8 years ago.
They are looking into it now. After talking to them, I discovered that they have reset the passcodes to my car and now lack the software to program them back, so it doesn't look like the problem was with the key at all. Is this something I need to take the car to the dealership to fix? I'm just confused as to why they would have reset the passcodes to my car without having the tools to reprogram them back in. I guess they don't have the right codes or something.
Expert:  john -aka eauto replied 8 years ago.
Itsis done thru a gm scanner or a tech 2 but he relearn i gave you early will usually work