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Home >> Cadillac >> 2006 >> Escalade EXT >> Repair and Diagnosis (Single Page) >> External Pages >> Different car >> Section 1133 (Cellular System, Entertainment System, And Navigation System) >> Diagnostic Information and Procedures >> Unable to Contact OnStar Call Center >> Circuit/System Verification
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Circuit/System Verification

WARNING: This page is about a different car, the 2008 GMC Sierra, 2008 GMC Cab & Chassis Sierra, 2008 Chevrolet Silverado, and 2008 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.
IMPORTANT:
  • It is important to have the vehicle in an open outside area where a cellular call can be successfully placed and GPS data can be received from satellites.
  • Placing an emergency call to the OnStar® Call Center should only be made if the diagnosis of the system leads to step 4. Immediately after an OnStar® advisor picks up the call, they should be told that this call is for diagnostic purposes only and there is no emergency.
  1. Press the OnStar® Call Center button. Verify a connection is not made with the OnStar® Call Center.
    • If a connection is made with the OnStar® Call Center, go to Diagnostic Aids.
  2. Listen for other tones or cellular messages rather than the normal progression tones or the Unable to Contact OnStar® prompt.
    • If no other tones or cellular messages are heard other than the normal progression tones or the Unable to Contact OnStar® prompt, go to Component Testing.
  3. Record all messages heard from the OnStar® Call Center button press.
  4. Press the OnStar® emergency button. Verify a connection to the OnStar® Call Center is made within 10 minutes.
    • If a connection is not made within specified time, go to Component Testing.
  5. Hear all messages during the course of the tests available, and contact the General Motors Technical Assistance Center.
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