Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Diagnosis Procedure
Regarding Wiring Diagram information, refer to WIRING DIAGRAM .
- CHECK HARNESS BETWEEN AV CONTROL UNIT AND MICROPHONE
- Turn ignition switch OFF.
- Disconnect AV control unit connector M102 and microphone connector R8.
- Check continuity between AV control unit connector M102 and microphone connector R8.
AV control unit Microphone Continuity Connector Terminal Connector Terminal M102 34 R8 1 Yes 35 4 36 2 - Check continuity between AV control unit connector M102 and ground.
AV control unit Ground Continuity Connector Terminal M102 34 - No 35
Is the inspection result normal?
YES
GO TO STEP 2 .
NO
Repair harness or connectors.
- CHECK MICROPHONE POWER SUPPLY
- Connect AV control unit connector M102 and microphone connector R8.
- Turn ignition switch ON.
- Check voltage between microphone connector R8 and ground.
Microphone Ground Voltage
(Approx.)(+) (-) Connector Terminal R8 4 - 5V
Is the inspection result normal?
YES
GO TO STEP 3 .
NO
Replace AV control unit. Refer to REMOVAL AND INSTALLATION .
- CHECK MICROPHONE SIGNAL
Check signal between terminals of AV control unit connector M102.
AV control unit connector M102 Condition Reference value (+) (-) Terminal Terminal 34 36 Speak into microphone. Is the inspection result normal?
YES
Replace AV control unit. Refer to REMOVAL AND INSTALLATION .
NO
Replace microphone. Refer to REMOVAL AND INSTALLATION .
NO RELATED
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.