Microphone Signal Circuit

MICROPHONE SIGNAL CIRCUIT


Description

Voice signals are transmitted from the microphone to the AV control unit using the microphone signal circuits.





MICROPHONE SIGNAL CIRCUIT


Diagnosis Procedure

Regarding Wiring Diagram information, refer to With Navigation System or With Navigation System.
1.CHECK HARNESS BETWEEN AV CONTROL UNIT AND MICROPHONE





1. Turn ignition switch OFF.
2. Disconnect AV control unit connector and microphone connector.
3. Check continuity between AV control unit harness connector
M102 (sedan) or M121 (coupe) (A) and microphone harness connector R7 (B).





4. Check continuity between AV control unit harness connector
M102 (sedan) or M121 (coupe) (A) and ground.






Are the continuity test results as specified?
YES - GO TO 2.
NO - Repair harness or connector.
2.CHECK MICROPHONE POWER SUPPLY





1. Connect AV control unit connector and microphone connector.
2. Turn ignition switch ON.
3. Check voltage between microphone harness connector R7 terminal 4 and ground.





Is voltage reading approx. 5 volts?
YES - GO TO 3.
NO - Replace AV control unit. Refer to AV Control Unit.
3.CHECK MICROPHONE SIGNAL





Check signal between AV control unit harness connector M102
(sedan) or M121 (coupe) terminals 43 and 59.







Are voltage readings as specified?
YES - Replace AV control unit. Refer to AV Control Unit.
NO - Replace microphone. Refer to With Navigation.