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Circuit/System Testing

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.