Disabled due to theft system

I'm afraid it's going to require the use of a scan tool to do this.
Here is the procedure

PROGRAMMING THEFT DETERRENT SYSTEM COMPONENTS

IMPORTANT:

* When replacing a body control module (BCM) with an GM Service Parts Operation (SPO) replacement part, set up the replacement BCM prior to the 10-Minute Relearn Procedure or the 30-Minute Relearn Procedure. Refer to Body Control Module (BCM) Programming/RPO Configuration in Programming and Setup.
* When replacing a BCM with an GM SPO replacement part, the module will learn the keys immediately. The existing powertrain control module (PCM) must learn the new fuel continue password when you replace the BCM.
* When replacing a PCM with a GM SPO replacement part, the new PCM will learn the incoming fuel enable password immediately after programming and upon receipt of a password message. A PCM which had been installed in another vehicle would have learned the fuel enable password of the other vehicle's BCM. Perform either the 10-Minute Relearn Procedure or the 30-Minute Relearn Procedure to learn the fuel enable password of the current vehicle's BCM.
* When performing either relearn procedure, all previously learned keys will be erased from the BCM memory.
* Additional keys may be learned. Refer to Adding Keys (Domestic).

10-Minute Relearn Procedure
Use this procedure after replacing the following components:

* The PASS-Key III (PK3) keys
* The BCM
* The PCM

1. Connect a scan tool to the vehicle. IMPORTANT: If replacing a BCM with a GM SPO replacement part, perform the procedure to setup a new BCM prior to the 10-Minute Relearn Procedure. Refer to Diagnostic System Check - Vehicle in Vehicle DTC Information.
2. Turn ON the ignition, with the engine OFF.
3. Insure that all power consuming devices are turned OFF on the vehicle.
4. With a scan tool, select Request Info. Under Service Programming System and follow the scan tool on-screen instructions.
5. Disconnect the scan tool from the vehicle and connect the scan tool to a Techline Terminal with the current Service Programming System (SPS) software.
6. On the Techline Terminal, select Service Programming System and follow the Techline Terminal on-screen instructions.
7. Disconnect the scan tool from the Techline Terminal and re-connect the scan tool to the vehicle.
8. With a master PASS-Key III key, turn ON the ignition with the engine OFF.
9. With a scan tool, select Program ECU under Service Programming System.
10. At this point the scan tool must remain connected for the duration of the 10-Minute Relearn Procedure.
11. Observe the scan tool, after approximately 10 minutes the scan tool will display "Programming Successful, Turn OFF Ignition". The vehicle is now ready to relearn the key information and/or the passwords on the next ignition switch transition from OFF to ON.
12. Turn OFF the ignition and wait 5 seconds.
13. With a master PASS-Key III key, start the vehicle. The BCM has now learned the key transponder information and the PCM has now learned the fuel continue password.
14. Turn OFF the ignition and wait 15 seconds minimum. IMPORTANT: Perform this step ONLY on vehicles with EXPORT configured BCMs.
15. With a second master PASS-Key III key, start the vehicle. The BCM has now learned the second master PASS-Key III key transponder information IMPORTANT: Perform this step ONLY on vehicles with EXPORT configured BCMs.
16. With a scan tool, clear any DTCs. 30-Minute Relearn Procedure Use this procedure after replacing the following components:

o The PASS-Key III (PK3) keys
o The BCM
o The PCM

1. With a master PASS-Key III key, turn ON the ignition, with the engine OFF. IMPORTANT:

o This procedure is not available on vehicles equipped with option code (Z49).
O If replacing a BCM with an GM SPO replacement part, perform the procedure to setup a new BCM prior to the 30-Minute Relearn Procedure.

2. Observe the STARTING DISABLED DUE TO THEFT message on the driver information center (DIC), after approximately 10 minutes the STARTING DISABLED DUE TO THEFT message on the DIC 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.
5. With a master PASS-Key III key, start the vehicle. The vehicle has now learned the key transponder information and the PCM has now learned the fuel continue password. IMPORTANT: The vehicle learns the key transponder information and/or passwords on the ignition switch transition from OFF to CRANK. You must turn the ignition OFF before attempting to start the vehicle.
6. With a scan tool, clear any DTCs.

I dont know of any reputable shop that will disarm security systems.

Roy

Hi and thanks for using 2carpros.com

The system isn't recognizing the key, as you already know. Now, what that means is the power control module (PCM) isn't receiving a correct key password from the body control module.

So with that said, there should be a diagnostic trouble code stored. If possible, scan the computer and let me know what code is found.

Here is a quick video showing how a scanner is used.

https://youtu.be/YV3TRZwer8k

Now, if you tried the 10 minute relearn process is performed, all keys previously learned may be lost. That takes us to the next step. The adding keys procedure needs to be performed. However, you still need the original key to do this. Take a look through this procedure and let me know if this is what you have already done.

ADDING KEYS (DOMESTIC)
ADDING KEYS (DOMESTIC)

IMPORTANT:
- To initiate, this procedures requires that a learned master key be available.
- A total of 10 master keys or valet keys may be programmed to a single vehicle.
- This procedure adds keys only. The procedure does not erase previously learned keys.
- The keys to be learned must duplicate the mechanical cut of the current key.
- If more than one valet key is to be learned, immediately precede each valet key with a learned master key.

1. With a previously learned master key, turn ON the ignition, with the engine OFF.
2. Turn OFF the ignition and remove the key.
3. 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.

I hope this helps. The 10 and 30 minutes relearn procedure is used when the BCM or PCM is replaced.

Let me know what happens.

Joe

If it was a security problem the car would not start or start and immediately stall. Check the fuse block under the hood and you will see a red wire going to a terminal at the fuse box. The nut on the cable to the stud loosens up and causes this problem, let us know how you make out

Marina, when you turn the key to on, and then to start what does the car do? Will it start and run a few seconds or does it do nothing in either position?