For 1990-2009 cars

### Removal procedure

Important: The vehicle communication interface module 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® 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.

1. Remove the instrument panel (I/P) accessory trim plate. Refer to Instrument Panel Accessory Trim Plate Replacement in Instrument Panel, Gages, and Console.
2. Remove the cupholder. Refer to Front Floor Console Cup Holder Replacement in Instrument Panel, Gages, and Console.
3. Remove the communication interface module bracket screws.
4. Remove the communication interface module bracket bolt.
5. Pull the module toward you.
6. Disconnect the cellular antenna cable (2) from the module.
7. Disconnect the GPS antenna cable (1) from the module by pulling outward on the circular metal sleeve.
8. Disconnect the 3 I/P harness connectors from the module.
9. Remove the module.

### Installation Procedure

1. If you are replacing the module, record the 10-digit STID number and the 11-digit ESN number from the labels on the new communication interface module.
2. Align the module to the I/P opening. Connect the 3 I/P harness connectors to the module.

Important: This GPS antenna cable connector may be damaged if not correctly aligned before installation.

3. Gently connect the GPS antenna cable (1) to the module by pushing inward on the circular metal sleeve.
4. Connect the cellular antenna cable (2) to the module.

Notice: Refer to Fastener Notice in the Preface section.

5. Align the bracket to the J-clip on the tie bar. Install the communication interface module bracket bolt.

Tighten
Tighten the bolt to 10 N·m (89 lb in).

6. Install the communication interface module bracket screws.

Tighten
Tighten the screws to 2 N·m (18 lb in).

7. Install the cupholder. Refer to Front Floor Console Cup Holder Replacement in Instrument Panel, Gages, and Console.
8. Install the I/P accessory trim plate. Refer to Instrument Panel Accessory Trim Plate Replacement in Instrument Panel, Gages, and Console.

Important: After replacing the communication interface module, you must reconfigure the OnStar® system. Failure to reconfigure the system will result in additional customer visit for repair.

9. Press and hold the white dot button until the OnStar® status LED turns from green to red, and back again to green.
10. Install a scan tool. Use the ID information menu to access the new ESN.
11. 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.
12. Press the blue OnStar® button to connect to the OnStar® call center:

12.1. | Tell the advisor that this vehicle has received a new communication interface module.

12.2. | Ask the advisor to add the new ESN to update the customer account.

12.3. | Follow any additional instructions from the OnStar® advisor.

12.4. | Ask the advisor to activate the OnStar® personal calling feature, if available.