Digital Radio Malfunction
Digital Radio Malfunction
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle (Diagnostic System Check - Vehicle) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (Strategy Based Diagnosis) for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions (Diagnostic Procedure Instructions) provides an overview of each diagnostic category.
Diagnostic Fault Information
Circuit/System Description
The digital radio receiver (DRR) receives an XM satellite radio signal via the digital radio antenna. This signal is passed to the DRR through the digital radio antenna coax. From the DRR, separate left and right channel audio signals are sent to the radio. The radio then processes these signals and passes the audio to the appropriate speakers or amplifier.
Reference Information
Schematic Reference
Radio/Navigation System Schematics (Radio/Navigation System Schematics)
Connector End View Reference
Component Connector End Views (Connector Views)
Description and Operation
Radio/Audio System Description and Operation (Radio/Audio System Description and Operation)
Electrical Information Reference
* Circuit Testing (Circuit Testing)
* Connector Repairs (Connector Repairs)
* Testing for Intermittent Conditions and Poor Connections (Testing for Intermittent Conditions and Poor Connections)
* Wiring Repairs (Wiring Repairs)
Scan Tool Reference
Control Module References (Programming and Relearning) for scan tool information
Special Tools
EL-48028 Digital Radio Test Antenna
Circuit/System Verification
1. Tune to a strong AM or FM station and verify each speaker is producing clear and even sound, with no distortion.
• If any speaker is not producing sound or the sound produced is distorted, refer to Speaker Malfunction (Speaker Malfunction).
2. With the vehicle outside in an area with an unobstructed view of the southern sky, tune to XM. Verify XM reception is clear and the No XM Signal message is not displayed on the radio.
• If the No XM Signal message is displayed or XM reception is poor, refer to Digital Radio Antenna Circuit Malfunction.
3. Radio tuned to XM, use the radio balance function to transfer audio between the left and right side of the vehicle. Verify clear and even sound is heard from each side of the vehicle.
• If either side of the vehicle is not producing sound or the sound produced is distorted, refer to Digital Radio Signal Circuit Malfunction.
Circuit/System Testing
Digital Radio Antenna Circuit Malfunction
1. Ignition OFF, disconnect the digital radio antenna coax from the digital radio receiver (DRR). Connect the EL-48028 to the DRR and move the vehicle outside in an area with an unobstructed view of the southern sky, tune to XM.
2. Ignition ON, radio tuned to XM, verify XM reception is clear and uninterrupted.
• If reception is not clear, replace the DRR.
3. Ignition OFF, reconnect the antenna coax to the DRR, disconnect the digital radio antenna coax from the digital radio antenna.
4. Ignition ON, test for 4.5-5.5 volts between the antenna coax center terminal and the coax outer shield.
• If not within the specified range, replace the antenna coax.
5. If all circuits test normal, replace the digital radio antenna.
Digital Radio Output Circuit Malfunction
1. Ignition OFF, disconnect the X2 harness connector at the radio.
2. Ignition ON, radio ON and tuned to XM, test for a varying mV AC voltage reading between the following signal circuit terminals listed below and ground.
* Left audio signal (+) - Connector X2, terminal J
* Right audio signal (+) - Connector X2, terminal H
* Audio common signal (-) - Connector X2, terminal K
• If the varying Mv A/C voltage reading is not present, test the signal circuit for a short to voltage, short to ground, or an open/high resistance. If the circuit tests normal, replace the DRR.
3. If all circuits test normal, test or replace the radio.
Repair Instructions
Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.
* Digital Radio Antenna Replacement (Digital Radio Antenna Replacement)
* Digital Radio Antenna Cable Replacement (Digital Radio Antenna Cable Replacement)
* Cellular Communications/Digital Radio Antenna Replacement (Cellular Communications/Digital Radio Antenna Replacement)
* Control Module References (Programming and Relearning) for radio or DRR replacement, setup, and programming