Onstar Vehicle Communication Unit (Vcu) Replacement

ONSTAR VEHICLE COMMUNICATION UNIT (VCU) REPLACEMENT

REMOVAL PROCEDURE




1. Open the rear compartment.

IMPORTANT: The vehicle communication unit (VCU) has a specific set of unique numbers that tie the module to each vehicle. These numbers, the 10-digit station identification and the 11-digit electronic serial number, are used by the National Cellular Network and OnStar(R) to identify the specific vehicle.Because these numbers are tied to the vehicle identification number of the vehicle, you must never exchange these parts with those of another vehicle.

2. Remove the cover from the OnStar(R) vehicle communication unit (VCU) by depressing the retainer tabs.




3. Remove the cellular coaxial cable from the VCU by pulling off.




4. Remove the screws from the DB-25 connector.




5. Remove the DB-25 connector from the VCU.




6. Release the retainer strap from the VCU using a small flat-bladed tool.
7. Remove the VCU from the rear compartment.

INSTALLATION PROCEDURE




1. Record the 11-Digit ESN number from the label on the new part.
2. Install the cellular coaxial cable to the VCU pressing into place until fully seated.




3. Install the DB-25 connector to the VCU pressing into place until fully seated.




4. Hand tighten the screws to the DB-25 connector.

NOTE: In order to avoid damage to the circuit board, do NOT over-tighten the thumb screws. Using your fingers, apply only a light pressure.




5. Position the (VCU) to the top of the vehicle interface unit (VIU).
6. Install the retainer strap to the VCU pressing into place until fully seated.




7. Install the cover to the VCU bay pressing the cover into place until fully seated.
8. Press and hold the white dot button until the OnStar(R) status LED turns from green to red, and back again to green.

IMPORTANT: After replacing the VCU, you must reconfigure the OnStar(R) system. Failure to reconfigure the system will result in an additional customer visit for repair.

9. Install a scan tool. Use the ID information menu to access the new ESN.
10. Move the vehicle to an open area that is away from tall buildings and with a clear view of unobstructed sky. Allow the vehicle to run for 10 minutes.
11. Press the blue OnStar(R) button to connect to the OnStar(R) call center
11.1. Tell the advisor that this vehicle has received a new VCU.
11.2. Ask the advisor to add the new ESN to update the customer's account.
11.3. Follow any additional instructions from the OnStar(R) advisor.
11.4. Ask the advisor to activate the OnStar(R) personal calling feature, if available.
12. Close the rear compartment.
13. Return the old VCU for core credit.