O.k.,have a master key cut by a GM dealer copying the cut of the valet key.Then you can take the master key and program it as following here to correct this fault.
30-Minute Relearn Procedure
Use this procedure after replacing the following components:
- The passkey III (PK3) keys
- The theft deterrent control module
- The PCM, see important above
1. With a master passkey III key (Black), turn ON the ignition, with the engine OFF.
IMPORTANT: This procedure is not available on vehicles equipped with option code (Z49 or BAE).
If replacing a theft deterrent control module with an GM SPO Replacement Part, perform the procedure to setup a new theft deterrent control module prior to the 30-minute relearn procedure.
2. Observe the Security telltale, 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.
5. With a master passkey III key, start the vehicle.
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