Base Audio

COMMUNICATION SIGNAL CIRCUIT (COUPE)


SATELLITE RADIO TUNER : Description

Communication signals are exchanged between the audio unit and satellite radio tuner using the communication circuits.





COMMUNICATION SIGNAL CIRCUIT (COUPE)


SATELLITE RADIO TUNER : Diagnosis Procedure

Regarding Wiring Diagram information, refer to Base Audio.
1.CHECK HARNESS - 1





1. Turn ignition switch OFF.
2. Disconnect satellite radio tuner (factory installed) connector B57 and audio unit connector M118.
3. Check continuity between satellite radio tuner (factory installed) harness connector B57 (A) terminal 28 and audio unit harness connector M118 (B) terminal 38.

Continuity should exist.

4. Check continuity between satellite radio tuner (factory installed) harness connector B57 (A) terminal 28 and ground.

Continuity should not exist.

Are continuity results as specified?
YES - GO TO 2
NO - Repair harness or connector.
2.CHECK HARNESS - 2





1. Check continuity between satellite radio tuner (factory installed) harness connector B57 (A) terminal 29 and audio unit harness connector M118 (B) terminal 39.

Continuity should exist.

2. Check continuity between satellite radio tuner (factory installed) harness connector B57 (A) terminal 29 and ground.

Continuity should not exist.

Are continuity results as specified?
YES - GO TO 3
NO - Repair harness or connector.
3.CHECK HARNESS - 3





1. Check continuity between satellite radio tuner (factory installed) harness connector B57 (A) terminal 30 and audio unit harness connector M118 (B) terminal 40.

Continuity should exist.

2. Check continuity between satellite radio tuner (factory installed) harness connector B57 (A) terminal 30 and ground.

Continuity should not exist.

Are continuity results as specified?
YES - GO TO 4
NO - Repair harness or connector.
4.CHECK REQ1 SIGNAL
1. Connect satellite radio tuner (factory installed) connector and audio unit connector.
2. Turn ignition switch to ACC





3. Check signal between satellite radio tuner (factory installed) harness connector B57 terminal 28 and ground with CONSULT-III or oscilloscope.





Are voltage readings as specified?
YES - GO TO 5
NO - Replace audio unit. Refer to Base Audio.
5.CHECK TXD SIGNAL





Check signal between satellite radio tuner (factory installed) harness connector B57 terminal 29 and ground with CONSULT-III or oscilloscope.





Are the voltage readings as specified?
YES - GO TO 6
NO - Replace satellite radio tuner. Refer to Base Audio.
6.CHECK RXD SIGNAL





Check signal between satellite radio tuner (factory installed) harness connector B57 terminal 30 and ground with CONSULT-III or oscilloscope.





Are the voltage readings as specified?
YES - Replace satellite radio tuner. Refer to Base Audio.
NO - Replace audio unit. Refer to Base Audio.