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Home >> Hummer >> 2010 >> H3 Alpha >> Repair and Diagnosis >> External Pages >> Different car >> Section 1770 (Cellular System, Entertainment System, And Navigation System) >> Diagnostic Information and Procedures >> Unable to Contact OnStar Call Center >> Circuit/System Testing
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Circuit/System Testing

WARNING: This page does not describe the selected car, but rather 8 other vehicles, including the 2011 GMC Yukon XL, 2011 GMC Yukon, 2011 Chevrolet Tahoe, 2011 Chevrolet Suburban, and 2011 Chevrolet Avalanche. However, it is still accessible from the selected car via links, so may be relevant.
NOTE:

The vehicle may be equipped with sectioned coax. Test each section and replace only the faulty section, not the entire length of coax.

  1. Ignition OFF, disconnect the GPS and cellular coax cable connector at the VCIM.
  2. Using the EL-49903-3 kit (EL-49903-5 adapter and EL-49903-4 coax cable), connect the EL-49903  kit to the VCIM.
  3. Ignition ON, wait 5 minutes, and then contact the OnStar call center consultant by pressing the blue OnStar button. A call center consultant should answer the call.
    • If the unit does not connect to the OnStar Call Center, replace the VCIM.
  4. Ignition OFF, disconnect the EL-49903  kit from the VCIM and perform the coax cable test on the coax cable between the VCIM and the cellular antenna.
    • If the coax cable does not pass the test, replace the coax cable.
  5. If all circuits test normal, replace the cellular antenna.
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