Communication Signal Circuit

COMMUNICATION SIGNAL CIRCUIT


Description

Satellite radio tuner and audio unit are connected with a serial communication. They transmit the operation signal from audio unit to satellite radio tuner.




COMMUNICATION SIGNAL CIRCUIT


Diagnosis Procedure

1.CHECK CONTINUITY COMMUNICATION SIGNAL (AUDIO-SAT) CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect satellite radio tuner connector and audio unit connector.
3. Check continuity between satellite radio tuner harness connector and audio unit harness connector.





4. Check continuity between satellite radio tuner harness connector and ground.





Is inspection result OK?
YES - GO TO 2.
NO - Repair harness or connector.
2.CHECK AUDIO UNIT
1. Connect audio unit connector.
2. Turn ignition switch ON.
3. Check voltage between audio unit harness connector and ground.





Is inspection result OK?
YES - GO TO 3.
NO - Replace audio unit.
3.CHECK SATELLITE RADIO TUNER
1. Turn ignition switch OFF.
2. Disconnect audio unit connector, and connect satellite radio tuner connector.
3. Turn ignition switch ON.
4. Check voltage between satellite radio tuner harness connector and ground.





Is inspection result OK?
YES - GO TO 4.
NO - Replace satellite radio tuner.
4.CHECK COMMUNICATION SIGNAL (SAT-AUDIO)
1. Turn ignition switch OFF.
2. Connect audio unit connector.
3. Turn ignition switch ON.
4. Check signal between satellite radio tuner harness connector and ground.





Is inspection result OK?
YES - GO TO 5.
NO - Replace satellite radio tuner.
5.CHECK COMMUNICATION SIGNAL (AUDIO-SAT)
Check signal between audio unit harness connector and ground.





Is inspection result OK?
YES - INSPECTION END
NO - Replace audio unit.