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Home >> Buick >> 2018 >> Enclave Base >> Repair and Diagnosis >> External Pages >> Different car >> Section 19 (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 is about a different car, the 2017 GMC Acadia Limited, 2017 Chevrolet Traverse, and 2017 Buick Enclave. 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  GM OnStar antenna diagnostic tool 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  GM OnStar antenna diagnostic tool kit EL-49903 from the VCIM and perform the coax cable test on the coax cable between the VCIM and the radio antenna.
    • If the coax cable does not pass the test, replace the coax cable.
  5. If all circuits test normal, replace the radio antenna.