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Circuit/System Testing

  1. Inspect the radio antennas for damage and proper mounting.
    • If damage is found, repair or replace as necessary.
  2. Inspect each radio antenna module grounding surface and the mounting hardware for any corrosion that may cause a poor ground.
    • If corrosion is noted, clean the grounding surfaces and hardware.
  3. Ignition OFF, disconnect the X2 harness connector at the right radio antenna module. Test for infinite resistance between the terminals listed below and ground.
    • Terminal 1
    • Terminal 2
    • If less than specified value, replace the appropriate antenna.
  4. Ignition OFF, disconnect the X2 harness connector at the left radio antenna module. Test for infinite resistance between the terminals listed below and ground.
    • Terminal 1
    • Terminal 2
    • If less than specified value, replace the appropriate antenna.
  5. Connect the X2 harness connector at the right antenna module and the X1 harness connector at the right antenna module.
  6. Ignition OFF, disconnect the X1 harness connector at the right radio antenna module.
  7. Radio ON, test for 10 - 12 volts between the signal circuit terminal 1 and ground.
    • If less than the specified value, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the radio.
  8. Radio tuned to FM, test for 4.5 - 8.5 volts on the FM composite signal terminal 2.
    • If less than specified range, test the signal circuit for a short to ground. If the circuit tests normal, replace the radio.
    • If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the radio.
  9. Ignition OFF, connect the harness connector at the right antenna module.
  10. Disconnect the coax cable from the left antenna module.
  11. Ignition ON, radio tuned to FM, test for 4.5 - 8.5 volts between the center terminal and the outer shield.
    • If less than specified range, test the coax for a short to ground. If the circuit tests normal, replace the right antenna module.
    • If greater than the specified range, test the coax for a short to voltage. If the circuit tests normal, replace the right antenna module.
    12. IMPORTANT: For steps 14-18, perform the tests on each of the disconnected coax cables.
  12. Ignition OFF, disconnect the coax cables at the radio and radio antenna modules.
  13. Test for infinite resistance between the antenna coax center terminal and ground.
    • If less than the specified value, replace the antenna coax.
  14. Test for less than 5 ohms on the antenna coax center terminal from end to end.
    • If greater than the specified range, replace the antenna coax.
  15. Test for less than 5 ohms on the antenna coax outer shield from end to end.
    • If greater than the specified range, replace the antenna coax.
  16. Test for infinite resistance between the coax center terminal and the outer shield.
    • If less than the specified value, replace the antenna coax.
  17. Radio ON, verify the radio reception has improved.
    • If there is still poor reception, replace the left antenna module.
  18. If all circuits test normal, replace the radio.
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