Circuit/System Testing

without Navigation System

NOTE:

You must perform the Circuit/System Verification before proceeding with Circuit/System Testing.

1. Ignition OFF/vehicle OFF, disconnect the GPS and cellular coax cable connector at the K73 Telematics Communication Interface Control Module.
2. Attach both leads of the EL-49903 - 1 OnStar test antenna to the EL-49903 - 5 combiner. Using the EL-49903 - 6 coax cable attach the grey connector to the combiner and the brown connector to the K73 Telematics Communication Interface Control Module. Place the test antenna on the roof of the vehicle, ignition ON.
3. 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.

   • Go to next step: If DTC B2462 is not set or the advisor can locate the vehicle 
4. 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.

   • Go to next step: If the coax cable passes the test 
5. Test or replace the T4G Cellular Phone, Navigation, and Digital Radio Antenna.

with Navigation System

NOTE:

You must perform the Circuit/System Verification before proceeding with Circuit/System Testing.

1. Ignition OFF/vehicle OFF, disconnect the T4G Cellular Phone, Navigation, and Digital Radio Antenna coax cable at the T15 Navigation Antenna Signal Splitter.
2. Attach both leads of the EL-49903 - 1 OnStar test antenna to the EL-49903 - 5 combiner. Using the EL-49903 - 7 coax cable attach one grey connector to the combiner and the other grey connector to the T15 Navigation Antenna Signal Splitter. Place the test antenna on the roof of the vehicle, ignition ON.
3. Verify DTC B2462 is not set or that the OnStar advisor can locate the vehicle.
   • If DTC B2462 is not set or the advisor can locate the vehicle 
   1. Test the coax cable between the T15 Navigation Antenna Signal Splitter 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.

      • Go to next step: If the coax cable passes the test
   2. Replace the T4G cellular phone, navigation and digital radio antenna.
   • Go to next step: If DTC B2462 is set or if the advisor can not locate the vehicle 
4. Ignition OFF/vehicle OFF, disconnect the GPS and cellular coax cable connector at the K73 Telematics Communication Interface Control Module.
5. Attach both leads of the EL-49903 - 1 OnStar test antenna to the EL-49903 - 5 combiner. Using the EL-49903 - 6 coax cable attach the grey connector to the combiner and the brown connector to the K73 Telematics Communication Interface Control Module. Place the test antenna on the roof of the vehicle, ignition ON.
6. 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.

   • Go to next step: If DTC B2462 is not set or the advisor can locate the vehicle. 
7. Ignition OFF/vehicle OFF.
8. Test the coax cable between the T15 Navigation Antenna Signal Splitter and the K73 Telematics Communication Interface Control Module. Refer to Component Testing.
   • If the coax cable does not pass the test. 

     Replace the coax cable.

   • Go to next step: If the coax cable passes the test. 
9. Ignition OFF/vehicle OFF, disconnect the blue GPS coax cable connector at the K74 Human Machine Interface Control Module.
10. Attach the EL-49903 - 1 OnStar test antenna blue connector to the K74 Human Machine Interface Control Module and place the test antenna on the roof of the vehicle.
11. Ignition ON/vehicle in Service Mode.
12. Verify DTC B2462 is not set or that the NO GPS symbol/message is not displayed on the radio.
    • If DTC B2462 is set or the NO GPS symbol/message is displayed 

      Replace the K74 Human Machine Interface Control Module

    • Go to next step: If DTC B2462 is not set or if the NO GPS symbol/message is not displayed. 
13. Ignition OFF/vehicle OFF.
14. Test the coax cable between the T15 Navigation Antenna Signal Splitter and the K74 Human Machine Interface Control Module. Refer to Component Testing.
    • If the coax cable does not pass the test. 

      Replace the coax cable.

    • Go to next step: If the coax cable passes the test. 
15. Test or replace the T15 Navigation Antenna Signal Splitter.