Without Navigation System

Vehicle OFF, disconnect the GPS and cellular coax cable connector at the K73 Telematics Communication Interface Control Module.
NOTE: You must perform Circuit/System Verification before proceeding with Circuit/System Testing.
Attach the EL-49903-1 OnStar® test antenna to the EL-49903-5 combiner. Using the EL-49903-6 brown -F coax cable attach the combiner to the K73 Telematics Communication Interface Control Module. Place the test antenna on the roof of the vehicle, vehicle in Service Mode.
Verify DTC B2462 is not set or that the OnStar® advisor can locate the vehicle.
- If DTC B2462 is set or the advisor can not locate the vehicle
  Replace the K73 Telematics Communication Interface Control Module.
- If DTC B2462 is not set or the advisor can locate the vehicle
Test the coax cable between the K73 Telematics Communication Interface Control Module and the T4G Cellular Phone, Navigation and Digital Radio Antenna. Refer to Component Testing .
- If the coax cable does not pass the test
  Replace the coax cable.
- If the coax cable passes the test
Test or replace the T4G Cellular Phone, Navigation and Digital Radio Antenna.