Rear Evaporator Temperature Sensor Circuit - Air Conditioning System (for Automatic Air Conditioning System)

AIR CONDITIONING: AIR CONDITIONING SYSTEM (for Automatic Air Conditioning System): B1417/17: Rear Evaporator Temperature Sensor Circuit

DTC B1417/17 - Rear Evaporator Temperature Sensor Circuit

DESCRIPTION

The rear evaporator temperature sensor is installed on the rear evaporator. It detects the rear evaporator temperature. The sensor sends a signal to the A/C amplifier. The resistance of the rear evaporator temperature sensor changes in accordance with the rear evaporator temperature. As the temperature decreases, the resistance increases. As the temperature increases, the resistance decreases.
The A/C amplifier applies voltage (5 V) to the rear evaporator temperature sensor and reads voltage changes as the resistance of the rear evaporator temperature sensor changes.






WIRING DIAGRAM





INSPECTION PROCEDURE

PROCEDURE

1. READ VALUE USING TECHSTREAM
(a) Connect Techstream to the DLC3.
(b) Turn the ignition switch to the ON position and turn Techstream on.
(c) Select the item below in the Data List, and read the display on Techstream.

Data List / Air Conditioner:





OK:
The display is as specified in the normal condition column.
Result:






C -- REPLACE A/C AMPLIFIER
B -- PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE
A -- Continue to next step.
2. INSPECT REAR EVAPORATOR TEMPERATURE SENSOR





(a) Remove the rear evaporator temperature sensor.
(b) Measure the resistance according to the value(s) in the table below.





Standard resistance:





NOTICE:
- Even slightly touching the sensor may change the resistance value. Be sure to hold the connector of the sensor.
- When measuring, the sensor temperature must be the same as the rear evaporator temperature.
HINT: As the temperature increases, the resistance decreases (see the graph).

NG -- REPLACE REAR EVAPORATOR TEMPERATURE SENSOR
OK -- Continue to next step.
3. CHECK HARNESS AND CONNECTOR (REAR EVAPORATOR TEMPERATURE SENSOR - A/C AMPLIFIER)





(a) Disconnect the rear evaporator temperature sensor connector.





(b) Disconnect the A/C 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 -- REPLACE A/C AMPLIFIER