Up to 08/2009

HEATING / AIR CONDITIONING: AIR CONDITIONING SYSTEM: B1462/62: Room Humidity Sensor Circuit
B1462/62 - Room Humidity Sensor Circuit

DESCRIPTION

The room humidity sensor detects cabin humidity. The voltage of the room humidity sensor changes in accordance with cabin humidity. The A/C amplifier reads changes in the room humidity sensor.

The room humidity sensor is integrated with the room temperature sensor.





WIRING DIAGRAM





INSPECTION PROCEDURE

PROCEDURE

1. READ VALUE USING TECHSTREAM

(a) Connect the Techstream to the DLC3.

(b) Turn the power switch on (IG).

(c) Turn the Techstream on.

(d) Enter the following menus: Body Electrical / Air Conditioner / Data List.

(e) Check the value(s) by referring to the table below.

Air Conditioner





OK:

The display is as specified in the Normal Condition column.

Result:





C -- REPLACE A/C AMPLIFIER Removal

B -- PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE Symptom Related Diagnostic Procedures
A -- Continue to next step.

2. CHECK HARNESS AND CONNECTOR (POWER SOURCE CIRCUIT)

(a) Disconnect the room humidity sensor connector.





(b) Measure the voltage according to the value(s) in the table below.

Standard Voltage:





Text in Illustration





NG -- CHECK HARNESS AND CONNECTOR (ROOM HUMIDITY SENSOR - A/C AMPLIFIER)
OK -- Continue to next step.

3. INSPECT ROOM HUMIDITY SENSOR

(a) Reconnect the room humidity sensor connector.





(b) Turn the power switch on (IG).

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

Standard Voltage:





NOTICE:
* Do not touch the room humidity sensor because it may be affected by body temperature and may not work properly.
* Hold the sensor only by its connector.
* The output voltage at the ambient temperature 25°C (77°F) is shown above.
HINT
As the humidity increases, the voltage increases (see the graph).

Text in Illustration





NG -- REPLACE ROOM HUMIDITY SENSOR
OK -- Continue to next step.

4. CHECK HARNESS AND CONNECTOR (ROOM HUMIDITY SENSOR - A/C AMPLIFIER)

(a) Disconnect the A/C amplifier connector.





(b) Disconnect the room humidity sensor connector.





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

Standard Resistance:





Text in Illustration





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR

OK -- REPLACE A/C AMPLIFIER Removal