LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Chevrolet >> 2011 >> Volt >> Repair and Diagnosis >> External Pages >> Different car >> Section 20 (Cellular System, Entertainment System, And Navigation System) >> Diagnostic Information and Procedures >> No Global Positioning System (GPS) Reception >> Circuit/System Testing (with Navigation Radio)
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Circuit/System Testing (with Navigation Radio)

WARNING: This page is about a different car, the 2012 Chevrolet Volt. 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.
  • The following verification requires the vehicle to be outside with an unobstructed view of the southern sky. Allow 5 minutes after turning the Vehicle in Service Mode for the GPS satellites to acquire vehicle signal.
  1. Vehicle OFF, disconnect the coax cable at the T15 navigation signal antenna splitter.
  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 navigation signal splitter. Place the test antenna on the roof of the vehicle, Vehicle in Service Mode.
  3. Verify that the customer GPS concern is still present.
    • If the GPS concern is not present 
    1. Vehicle OFF, disconnect the EL-49903  GM OnStar antenna diagnostic tool kit from the K73 telematics communication interface control module
    2. Connect the GPS, T15 navigation antenna signal splitter, and cellular coax cable connector at the K73 telematics communication interface control module.
    3. Disconnect the coax cable at the T4G cellular phone, navigation and digital radio antenna.
    4. 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.

      • If the coax cable passes the test
    5. Replace the T4G cellular phone, navigation and digital radio antenna.
    • If the GPS concern is still present 
  4. Vehicle OFF, disconnect the coax cable between the T15 navigation antenna signal splitter and the K73 telematics communication interface control module.
  5. 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 telematics communication interface module. Place the test antenna on the roof of the vehicle, Vehicle in Service Mode
  6. Verify that an OnStar advisor can locate the vehicle after performing a blue button press.
    • If the advisor can not locate the vehicle 

      Replace the K73 telematics communication interface control module.

    • If the advisor can locate the vehicle 
  7. Vehicle OFF.
  8. Test the coax cable between the navigation 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.

    • If the coax cable passes the test 
  9. Vehicle OFF, disconnect the coax cable between the T15 navigation signal splitter and the A11 radio.
  10. Connect the test antenna to the radio and place the test antenna on the roof of the vehicle.
  11. Vehicle in Service Mode.
  12. Verify that the NO GPS symbol/message is not displayed on the radio.
    • If the NO GPS symbol/message is displayed 

      Replace the A11 Radio

    • If the NO GPS symbol/message is not displayed 
  13. Vehicle OFF.
  14. Test the coax cable between the T15 navigation antenna signal splitter and the A11 radio. Refer to Component Testing.
    • If the coax cable does not pass the test 

      Replace the coax cable.

    • If the coax cable passes the test 
  15. Replace the T15 navigation antenna signal splitter.
scientia non olet · About LEMON Manuals