Infrared Ray Sensor Communication Malfunction - Air Conditioning System

AIR CONDITIONING: AIR CONDITIONING SYSTEM: B1492/92: Infrared Ray Sensor Communication Malfunction
B1492/92 - Infrared Ray Sensor Communication Malfunction

DESCRIPTION

This circuit consists of the infrared ray sensor and the air conditioning amplifier. The infrared ray sensor, which is installed on the rear roof, detects human body temperature and control the heater and air conditioner "AUTO" mode in 4 zones. Signals are transmitted to the air conditioning amplifier via the LIN communication line. This DTC is output when communication between the infrared ray sensor and the air conditioning amplifier stops for 10 seconds or more. If the LIN communication system malfunctions, the air conditioning amplifier does not operate even if the infrared ray sensor is normal.





WIRING DIAGRAM





INSPECTION PROCEDURE

PROCEDURE

1. CHECK HARNESS AND CONNECTOR (INFRARED RAY SENSOR - AIR CONDITIONING AMPLIFIER)





(a) Disconnect the X13 infrared ray sensor connector.

(b) Disconnect the L76 air conditioning amplifier connector.

(c) Measure the resistance according to the value(s) in the table below.

Standard resistance:





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.

2. REPLACE INFRARED RAY SENSOR

(a) Replace the infrared ray sensor with a new or properly functioning one Removal.

(b) Operate the infrared ray sensor to check that it functions properly.

OK:

Infrared ray sensor function operates normally.

Result





B -- END (INFRARED RAY SENSOR IS FAULTY)

A -- REPLACE AIR CONDITIONING AMPLIFIER Removal