Optical Sensor

OPTICAL SENSOR

Component Description


COMPONENT DESCRIPTION






The optical sensor (1) is located in the center of the defroster grille. It detects sunload entering through windshield by means of a photo diode. The sensor converts the sunload into a current value which is then input into the front air control.

OPTICAL INPUT PROCESS

The front air control includes a processing circuit which averages the variations in detected sunload over a period of time. This prevents adjustments in the ATC system operation due to small or quick variations in detected sunload.
For example, consider driving along a road bordered by an occasional group of large trees. The sunload detected by the optical sensor will vary whenever the trees obstruct the sunlight. The processing circuit averages the detected sunload over a period of time, so that the (insignificant) effect of the trees momentarily obstructing the sunlight does not cause any change in the ATC system operation. On the other hand, shortly after entering a long tunnel, the system will recognize the change in sunload, and the system will react accordingly.


Optical Sensor Diagnosis Procedure

Regarding Wiring Diagram information, Automatic Air Conditioning.

DIAGNOSTIC PROCEDURE FOR OPTICAL SENSOR






SYMPTOM: Optical sensor circuit is open or shorted. Using the
CONSULT, DTC B257F or B2580 is displayed. Without a CONSULT, code 50 or 52 is indicated on front air control as a result of conducting self-diagnosis.

1. CHECK CIRCUIT CONTINUITY BETWEEN OPTICAL SENSOR AND FRONT AIR CONTROL






1.Turn ignition switch OFF.
2.Disconnect front air control connector and optical sensor connector.
3.Check continuity between optical sensor harness connector
M302 (B) terminals 1 and 2 and front air control harness connector M50 (C) terminal 38 and M49 (A) terminal 1.
1 - 1: Continuity should exist.
2 - 38: Continuity should exist.

4.Check continuity between optical sensor harness connector
M302 (B) terminal 1 and 2 and ground.
1, 2 - Ground: Continuity should not exist.
Is the inspection result normal?
YES- GO TO 2.
NO- Repair harness or connector.

2. CHECK CIRCUIT CONTINUITY BETWEEN OPTICAL SENSOR AND BCM






1.Disconnect BCM connector.
2.Check continuity between optical sensor harness connector
M302 (B) terminal 3 and BCM harness connector M18 (A) terminal 18.
3 - 18: Continuity should exist.
3.Check continuity between optical sensor harness connector
M302 (B) terminal 4 and ground.
3 - Ground: Continuity should not exist.
Is the inspection result normal?
YES- Replace optical sensor. Service and Repair.
NO- Repair harness or connector.