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Home >> Pontiac >> 2002 >> Aztek AWD >> Repair and Diagnosis >> External Pages >> Different car >> Section 1342 (Cellular Communication System) >> Repair Instructions >> OnStar Vehicle Communication Unit (VCU) Replacement >> Installation Procedure
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Installation Procedure

WARNING: This page does not describe the selected car, but rather 6 other vehicles, including the 2002 GMC Yukon XL, 2002 GMC Yukon, 2002 Chevrolet Tahoe, 2002 Chevrolet Suburban, and 2002 Cadillac Escalade EXT. However, it is still accessible from the selected car via links, so may be relevant.
  1. Record the 11-digit ESN from the label on the new VCU module.
  2. Fig 1: Installing Screw
    GM661523Courtesy of GENERAL MOTORS CORP.
    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.
  3. Install the VCU to the bracket.
  4. Connect the electrical connectors to the VCU.
  5. NOTE: Refer to FASTENER NOTICE .
  6. Install the screw.

    Tighten:  Tighten the screw to 9 N.m (80 lb in).

  7. Install the IP cluster harness.
  8. Install the IP trim panel. Refer to TRIM PANEL REPLACEMENT - INSTRUMENT PANEL (I/P) UPPER .
  9. IMPORTANT: After replacing the VCU, you must reconfigure the OnStar® system. Failure to reconfigure the system will result in an additional customer visit for repair.
  10. Press and hold the white dot button until the OnStar® status LED turns from green to red, and back again to green.
  11. Install a scan tool. Use the ID information menu to access the new ESN.
  12. 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.
  13. Press the blue OnStar® button to connect to the OnStar® call center
    1. Tell the advisor that this vehicle has received a new VCU.
    2. Ask the advisor to add the new ESN to update the customer's account.
    3. Follow any additional instructions from the OnStar® advisor.
    4. Ask the advisor to activate the OnStar® personal calling feature, if available.
  14. Return the old VCU for core credit.