Bose W/ Color W/ Navi W/Rear Control

U1243 DISPLAY UNIT





DTC Logic









Diagnosis Procedure
Regarding Wiring Diagram information, Bose W/ Color W/ Navi W/Rear Control.
1.CHECK DISPLAY UNIT POWER SUPPLY AND GROUND CIRCUIT
Check display unit power supply and ground circuit. Bose W/ Color W/ Navi W/Rear Control.
Is inspection result OK?
YES - GO TO 2.
NO - Repair malfunctioning parts.
2.CHECK CONTINUITY OF COMMUNICATION CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect display unit connector M142 and AV control unit connector M137.





3. Check continuity between display unit harness connector M142 (A) terminals 9, 10 and AV control unit harness connector M137 (B) terminals 45 and 61.





4. Check continuity between display unit harness connector M142 (A) terminals 9, 10 and ground.





Are continuity results as specified?
YES - GO TO 3.
NO - Repair harness or connector.
3.CHECK COMMUNICATION SIGNAL
1. Connect display unit connector and AV control unit connector.
2. Turn ignition switch ON.





3. Check signal between display unit harness connector M142 terminal 9 and ground with an oscilloscope or CONSULT-III.





Are voltage readings as specified?
YES - GO TO 4.
NO - Replace AV control unit. Bose W/ Color Display.
4.CHECK COMMUNICATION SIGNAL





Check signal between display unit harness connector M142 terminal 10 and ground with an oscilloscope or CONSULT-III.





Are voltage readings as specified?
YES - Inspection End.
NO - Replace display unit. Bose W/ Color W/ Navi W/Rear Control.