Tech Tip: GM Instrument Panel Cluster (IPC) Relearn – UnderhoodService

Tech Tip: GM Instrument Panel Cluster (IPC) Relearn

You may experience a problem where a GM vehicle will not start after a replacement IPC has been installed. In this tech tip, you will learn the procedure to enable the new IPC and the ECC to communicate.

You may experience a problem where a GM vehicle will not start after a replacement Instrument Panel Cluster (IPC) has been installed.

Follow the security system (Passlock) Auto Learn procedure outlined below to enable the replacement IPC and the ECC to communicate and learn a new password.

1. Before replacing the ECC, document all existing DTCs prior to the repair.

2. Place the ignition key in the On position.

3. Using a suitable scan tool, clear all security system (Passlock) and powertrain DTCs.

4. Rotate the ignition key to the Crank position (attempt to start the vehicle). The engine will attempt to start and stall. Leave the key in the On position.

5. Wait 10 minutes. Observe the security light. It will flash for a few seconds and remain on for 10 minutes.

6. Turn the ignition key to the Off position after the Security light goes out. Wait for at least 30 seconds.

7. Repeat steps 4-6 two more times. A new password is now ready to be communicated to the security system (Passlock) sensor, IPC and ECC with the next ignition cycle (start attempt).

8. If the engine starts, the Password Auto Learn procedure is complete. If the engine fails to start, perform the relearn procedure again.

9. Check for any DTCs. Repair as necessary and clear if present.

Refer to the vehicle’s service manual for detailed relearn procedures specific to your application.

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