• Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
• Review Strategy Based Diagnosis for an overview of the diagnostic approach.
• Diagnostic Procedure Instructions provides an overview of each diagnostic category.

The radio antenna for AM and FM radio reception is connected to the radio with a coaxial cable.

• Ignition ON/Vehicle in Service Mode.
• Battery voltage must be between 9–16 V.

The radio detects a short to ground in the antenna signal circuit center conductor.

The radio detects an open in the antenna signal circuit center conductor.

The radio detects a short to battery in the antenna signal circuit center conductor.

Radio reception may be poor or not available.

• The condition responsible for setting the DTC no longer exists.
• A history DTC will clears after 50 consecutive malfunction-free ignition cycles have occurred.

Poor AM and FM radio reception is dependent on multiple influences, some of which may not be vehicle related. Areas which have high RF traffic or block the signal path may cause a degradation in radio reception. Radio reception may also be influenced by items within the vehicle, but are not part of the radio system. Such examples are aftermarket electrical accessories or other items which may generate noise in the vehicle electrical system.

Radio/Navigation System Schematics

Master Electrical Component List

Radio/Audio System Description and Operation

• Circuit Testing
• Connector Repairs
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs

Control Module References for scan tool information

1. Inspect the antenna for proper mounting or physical damage.
• If damage is found

  Repair or replace as necessary

• If no damage is found
2. Ignition ON/Vehicle in Service Mode, A11 Radio ON.
3. Verify station reception is normal when tuned to several known good AM and FM stations.
• If AM or FM reception is poor.

  Refer to Circuit/System Testing

• If reception is normal
4. All OK.

1. Ignition OFF, disconnect the radio antenna coax cable from the A11 Radio and from the T2RR Antenna – Rear Roof.
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 radio antenna coax cable to the A11 Radio.
4. Ignition ON, A11 Radio ON.
5. Test for 10 V or greater between the antenna coax cable center terminal at the T2RR Antenna – Rear Roof and chassis ground.
• If less than 10 V

  Replace the A11 Radio.

• If 10 V or greater
6. Test or replace the T2RR Antenna – Rear Roof.

1. Ignition OFF/Vehicle OFF, disconnect the coax cable at both components.
2. Test for less than 5 Ω between coax cable center terminal end to end.
• If 5 Ω or greater

  Replace the coax cable

• If less than 5 Ω
3. Test for less than 5 Ω between the coax cable outer shield end to end.
• If 5 Ω or greater

  Replace the coax cable

• If less than 5 Ω
4. Test for infinite resistance between the coax cable center terminal and the coax cable outer shield.
• If less than infinite resistance

  Replace the coax cable

• If infinite resistance
5. All OK

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

• High Frequency Antenna Replacement
• Control Module References for radio replacement, programming, and setup.