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Home >> Chevrolet >> 2008 >> HHR SS, Automatic >> Repair and Diagnosis >> External Pages >> Different car >> Section 249 (Cellular Systems, Entertainment Systems & Navigation Systems) >> Diagnostic Information and Procedures >> Unable to Contact OnStar Call Center >> Circuit/System Testing
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Circuit/System Testing

WARNING: This page is about a different car, the 2010 Chevrolet HHR. However, it is still accessible from the selected car via links, so may be relevant.
  1. Ignition OFF, disconnect the cellular antenna coax from the CIM module and the cellular antenna.
  2. Ignition ON, test for less than 1 volt between the antenna coax center terminal and ground.
    • If greater than the specified range, replace the antenna coax.
  3. Ignition ON, test for less than 1 volt between the antenna coax outer shield and ground.
    • If greater than the specified range, replace the antenna coax.
  4. Test for infinite resistance between the antenna coax center terminal and ground.
    • If less than the specified value, replace the antenna coax.
  5. Test for infinite resistance between the antenna coax outer shield and ground.
    • If less than the specified value, replace the antenna coax.
  6. Test for less than 5 ohms at the cellular antenna coax center terminal from end to end.
    • If greater than specified value, replace the cellular antenna coax cable.
  7. Test for less than 5 ohms at the cellular antenna coax outer shield from end to end.
    • If greater than specified value, replace the cellular antenna coax cable.
  8. Test for infinite resistance between the antenna coax center terminal and the outer shield.
    • If less than specified value, replace the cellular antenna coax cable.
  9. If coax cable tests normal, replace the cellular antenna.
  10. Press the OnStar® Call Center button. Verify the system connects to OnStar® call center.
    • If a connection is not made to the OnStar® call center, replace the CIM.