U124C

U124C CD CHANGER





Description
Refer to System Description.




DTC Logic

DTC DETECTION LOGIC









Diagnosis Procedure
1.CHECK CD CHANGER POWER SUPPLY AND GROUND CIRCUIT
Check CD changer power supply and ground circuit. Refer to CD Changer.
Do power and ground check OK?
YES >> GO TO 2
NO >> Repair power supply or ground circuit.
2.CHECK COMMUNICATION CIRCUIT CONTINUITY
1. Turn ignition switch OFF.
2. Disconnect CD changer connector M42 and AV control unit connector M48.





3. Check continuity between CD changer harness connector M42
(A) terminals 8, 9 and 10 and AV control unit harness connector
M48 (B) terminals 69, 70 and 72.





4. Check continuity between CD changer harness connector M42
(A) terminals 8, 9, 10 and ground.

8, 9, 10 - Ground : Continuity should not exist.

Are the continuity test results as specified?
YES >> GO TO 3
NO >> Repair harness or connector.
3.CHECK REQUEST SIGNAL
1. Connect CD changer connector and AV control unit connector.
2. Turn ignition switch ON.





3. Check signal between CD changer harness connector M42 terminal 8 and ground.





8 - Ground

Are the voltage readings as specified?
YES >> GO TO 4
NO >> Replace CD changer. Refer to CD Changer.
4.CHECK COMMUNICATION SIGNAL





Check signal between CD changer harness connector M42 terminal
9 and ground.

9 - Ground





Are the voltage readings as specified?
YES >> GO TO 5
NO >> Replace CD changer. Refer to CD Changer.
5.CHECK COMMUNICATION SIGNAL





Check signal between CD changer harness connector M42 terminal
10 and ground.

10 - Ground





Are the voltage readings as specified?
YES >> Inspection End.
NO >> Replace AV control unit. Refer to Bose Audio With Navigation.