Vehicle Communication Unit (VCU)
- Record the ESN number from the label on the new part, (11 digits, no letters).
- Install the new VCU.
- After replacement, press and hold the OnStar "End Call" button (black with white dot); watch for the OnStar® status light to change from Green to Red to Green.
- Move the vehicle outside and let it run for ten minutes.
- Press the blue OnStar® button to connect to OnStar®. Tell the advisor that this vehicle has a new VCU and a new ESN to put in the customers account and that the vehicle requires a "Reconfiguration". Follow any additional instructions given by the Advisor.
- The old VCU must be returned for core credit. Use the address label included in the original box. Failure to return core will result in a debit.