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Poor or No Sound With XM Radio (Audio Unit Can Display XM Channels)

Poor or no sound with XM radio (audio unit can display XM channels)

NOTE: Check the radio reception in an open area. Poor reception/interference can be caused by tall buildings, mountains, or high-voltage power lines are nearby.

1. Turn the ignition switch to ACC (I).
2. Turn on the audio unit and select XM radio.
3. Check for an error message on the display.

Are there any messages displayed?

YES - Go to error code list. Error Codes

N0 -
- With navigation: Go to step 7.
- Without navigation: Go to step 4.

4. Disconnect audio unit connector B (14P) and the XM receiver connector A (14P).




5. Check for continuity between XM receiver connector A (14P) and body ground according to the table. Then check for continuity between the same terminals listed in the table and audio unit connector B (14P) No. 4 terminal (the harness shield).

Is there continuity?

YES - Repair a short in the wire between the audio unit and the XM receiver or short between the shield wire (replace the appropriate shielded harness).

NO - Go to step 6.




6. Check for continuity between XM receiver connector A (14P) and audio unit connector B (14P) according to the table.

Is there continuity?

YES - Substitute a known-good XM receiver, then reconnect all connector and recheck. If the symptom/indication goes away, replace the original XM receiver. If symptom/indication is still present, replace the audio unit

NO - Repair open in the wire between audio unit and XM receiver.

7. Disconnect CD changer connector B (14P) and XM receiver connector.




8. Check for continuity between XM receiver connector A (14P) and body ground according to the table. Then check for continuity between the same terminals listed in the table and CD changer connector B, (14P) No. 4 terminal (the harness shield).

Is there continuity?

YES - Repair a short in the wire between the CD changer and the XM receiver or a short between the shield wire (replace the appropriate shielded harness).

NO - Go to step 9.




9. Check for continuity between XM receiver connector A (14P) and CD changer connector B (14P) according to the table.

Is there continuity?

YES - Go to step 10.

NO - Repair open in the wire between CD changer and XM receiver.

10. Disconnect CD changer connector A (18P) and audio unit connector B (14P).




11. Check for continuity between CD changer connector A (18P) and body ground according to the table.
Check for continuity between the same terminals listed in the table and the XM receiver connector A (18P) No. 11 terminal (the harness shield).

Is there continuity?

YES - Repair the short between the CD changer and the audio unit, or replace the appropriate shield harness.

NO - Go to step 12.




12. Check for continuity between the CD changer connector A (18P) and audio unit connector B (14P) according to the table.

Is there continuity?

YES - Substitute a known-good XM receiver and retest. If the symptom/indicated goes away replace XM receiver. If the symptom/indicated is still present replace the audio unit.

NO - Repair an open in the wire between the CD changer and the audio unit.