Nissan Frontier. Manual - part 875
HAC-54
< DTC/CIRCUIT DIAGNOSIS >
[AUTOMATIC AIR CONDITIONER]
OPTICAL SENSOR
OPTICAL SENSOR
Component Description
INFOID:0000000009478298
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 aver-
ages 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 accord-
ingly.
Optical Sensor Diagnosis Procedure
INFOID:0000000009478299
Regarding Wiring Diagram information, refer to
HAC-63, "Wiring Diagram - Automatic Air Conditioner"
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 conduct-
ing self-diagnosis.
1.
CHECK CIRCUIT CONTINUITY BETWEEN OPTICAL SENSOR AND FRONT AIR CONTROL
AWIIA0169ZZ
AWIIA1076GB