Poor Sound With XM Radio
Poor sound with XM radio1. Turn the ignition switch OFF.
2. Disconnect the audio unit connector B (14P)and XM receiver connector A (14P).
3. Check for continuity between the XM receiver connector A (14P) and body ground according to the table.
Is there continuity?
YES - Repair short in the wire between the audio unit and the XM receiver.
NO - Go to step 4.
4. Check for continuity between the XM receiver connector A (14P) and the audio unit connector B (14P) according to the table.
Is there continuity?
YES - Go to step 5.
NO - Repair open in the wire between the audio unit and the XM receiver.
5. Turn the ignition switch to the ACC (I).
6. Check for voltage between XM receiver connector A (14P) terminals A1 and A7 and body ground, individually.
Is there battery voltage?
YES - Go to step 7.
NO - Repair open in the wire between fuse No. 32 (7.5 A) in the under-dash fuse/relay box and the XM receiver.
7. Check for continuity between XM receiver connector A (14P)terminal A11 and body ground.
Is there continuity?
YES - Go to step 8.
NO - Repair open in the wire between the XM receiver and G604. If the wire is OK, repair G604.
8. Substitute a known-good XM receiver, then reconnect all connectors and test the XM radio.
Is the sound normal?
YES - Replace the XM receiver.
NO - Replace the audio unit.