Diagnosis Procedure
1.
CHECK MICROPHONE SIGNAL CIRCUIT AND MICROPHONE POWER SUPPLY CIRCUIT CONTINUITY
Turn ignition switch OFF.
Disconnect TCU connector and microphone connector.
Check continuity between TCU connector and microphone connector.
TCU
Microphone
Continuity
Connector
Terminal
Connector
Terminal
M35
17
R8
8
Existed
18
3
Check the continuity between TCU connector and ground.
TCU
Ground
Continuity
Connector
Terminal
M35
18
Not existed
17
Is the inspection result normal?
.
Repair or replace harness or connectors.
2.
CHECK MICROPHONE POWER SUPPLY VOLTAGE
Connect TCU connector and microphone connector.
Turn ignition switch ON.
Check voltage between TCU connector and ground.
(+)
(−)
Voltage
(Approx.)
TCU
Connector
Terminal
M35
18
Ground
5.0 V
Is the inspection result normal?
.
Replace TCU. Refer to
Removal & Installation
.
3.
CHECK MICROPHONE SIGNAL
Check signal between TCU connector and ground.
(+)
(−)
Condition
Reference value
TCU
Connector
Terminal
M35
17
Ground
Speak into microphone.
Is the inspection result normal?
Replace TCU.Refer to
Removal & Installation
.
Replace microphone.Refer to
Removal and Installation
.