Operation CHARM: Car repair manuals for everyone.

Control Unit Replacement

Control Unit Replacement







The dealer troubleshooting process for OnStar consists of these items:.

- Check fuses for OnStar system.
- Check continuity of wiring.
- OnStar diagnostic check.
- Vehicle interface functionality check.

If the OnStar hardware in a vehicle has been replaced, the dealer must contact OnStar technical support to register the new OnStar control unit is STID and ESN.

The dealer will do the MIN programming and confirmation process if a new MIN is provided by OnStar technical support.

Once the dealer has notified OnStar of the new ESN and MIN, and done the MIN programming process if necessary, the dealer will press the blue OnStar button and request a configuration for the vehicle.