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Circuit/System Testing

WARNING: This page is about a different car, the 2017 GMC Acadia. However, it is still accessible from the selected car via links, so may be relevant.
  1. Ignition OFF, disconnect the radio antenna coax cable from the A11 Radio and from the T2RR Antenna - Roof Rear.
  2. Verify the antenna coax cable passes the coax cable component test. Refer to Component Testing.
    • If the coax cable does not pass the test 

      Replace the antenna coax cable

    • If the coax cable passes the test 
  3. Connect the antenna coax cable to the T2RR Antenna - Roof Rear.
  4. Test for infinite resistance between the coax cable center terminal and the coax cable outer shield at the radio end of the coax cable.
    • If less than infinite resistance 

      Replace the radio antenna base.

    • If infinite resistance 
  5. Test for less than 10 Ω between the coax cable outer shield and ground at the radio end of the coax cable.
    • If 10 Ω or greater 
    1. Clean the mounting surface of the radio antenna base.
    2. Connect the antenna coax cable to the T2RR Antenna - Roof Rear.
    3. Test for less than 10 Ω between the coax cable outer shield and ground at the radio end of the coax cable.
      • If 10 Ω or greater, replace the antenna base.
      • If less than 10 Ω, connect all harness connectors. Verify station reception is normal when tuned to several known good AM and FM stations. If AM or FM reception concerns are still present, replace the A11 Radio.
    • If less than 10 Ω 
  6. Test or replace the A11 Radio.