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.
Optical sensor System Inspection
- CHECK OPTICAL SENSOR INPUT SIGNAL
Select "BCM" in CONSULT-II. Using "OPTICAL SENSOR" data from "DATA MONITOR", check difference in the voltage when the auto light sensor is illuminated and not illuminated.
- Illuminated
- Optical sensor : 3.1V or more
- Not illuminated
- Optical sensor : 0.6V or less
CAUTION: Optical sensor must be securely subjected to work lamp light. If the optical sensor is insufficiently illuminated, the measured value may not satisfy the standard.OK or NG
- OK : INSPECTION END
- NG : GO TO 2.
- CHECK OPTICAL SENSOR POWER SUPPLY CIRCUIT
- Turn ignition switch OFF.
- Disconnect BCM connector and optical sensor connector.
- Check continuity (open circuit) between BCM harness connector M36 terminal 45 (BR/Y) and optical sensor harness connector M16 terminal 1 (BR/Y).
- Continuity should exist.
- Check continuity (short circuit) between BCM harness connector M36 terminal 45 (BR/Y) and ground.
- Continuity should not exist.
OK or NG
- OK : GO TO 3.
- NG : Repair harness or connector.
- CHECK OPTICAL SENSOR POWER SUPPLY CIRCUIT
- Check continuity (open circuit) between BCM harness connector M36 terminal 38 (W) and optical sensor harness connector M16 terminal 2 (W).
- Continuity should exist.
- Check continuity (short circuit) between BCM harness connector M36 terminal 38 (W) and ground.
- Continuity should not exist.
OK or NG
- OK : GO TO 4.
- NG : Repair harness or connector.
- Check continuity (open circuit) between BCM harness connector M36 terminal 38 (W) and optical sensor harness connector M16 terminal 2 (W).
- CHECK OPTICAL SENSOR POWER SUPPLY CIRCUIT
- Check continuity (open circuit) between BCM harness connector M37 terminal 53 (P) and optical sensor harness connector M16 terminal 3 (P).
- Continuity should exist.
- Check continuity (short circuit) between BCM harness connector M37 terminal 53 (P) and ground.
- Continuity should not exist.
OK or NG
- OK : GO TO 5.
- NG : Repair harness or connector.
- Check continuity (open circuit) between BCM harness connector M37 terminal 53 (P) and optical sensor harness connector M16 terminal 3 (P).
- CHECK OPTICAL SENSOR VOLTAGE
- Connect BCM connector.
- Turn ignition switch ON.
- Check voltage between BCM harness connector M36 terminal 45 (BR/Y) and ground.
- Approx. 5V should exist.
OK or NG
- OK : Replace the optical sensor.
- NG : Replace BCM. Refer to REMOVAL AND INSTALLATION OF BCM .
Use the Manual With the Right Hardware
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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.
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