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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 >> OnStar Global Positioning System (GPS) Data Not Current or Inaccurate >> 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.
  1. Ignition OFF, disconnect the GPS and cell coax cable connector at the vehicle communication interface module.
  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 vehicle communication interface module, place the test antenna on the roof of the vehicle.
  3. Ignition ON, wait 5 minutes, then contact the OnStar call center consultant by pressing the blue OnStar button. A call center consultant should answer the call, ask the consultant to verify the vehicle location to confirm the GPS system is functioning.
    • If the OnStar GPS does not function, replace the vehicle communication interface module.
  4. Reconnect the coax cable to the vehicle communication interface module. Disconnect the coax cable from the radio antenna.
  5. Test for 4.5 - 5.5 V between the coax cable center conductor and the outer shield.
    • If not within the specified range, replace the coax cable.
  6. If all circuits test normal, replace the radio antenna.
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