Evaporator Temperature Sensor Circuit - Air Conditioning System

AIR CONDITIONING: AIR CONDITIONING SYSTEM: B1413/13: Evaporator Temperature Sensor Circuit
B1413/13 - Evaporator Temperature Sensor Circuit

DESCRIPTION

This sensor detects the evaporator temperature and sends the appropriate signals to the A/C amplifier. It is used for frost prevention, temperature and time-lag air flow control.

WIRING DIAGRAM

INSPECTION PROCEDURE

PROCEDURE

1. INSPECT AIR CONDITIONING AMPLIFIER (TEA - SGA)

(a) Remove the air conditioning amplifier with connectors still connected.

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

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

Standard Voltage:

HINT
As the temperature increases, the voltage decreases.

Result:

C -- REPLACE AIR CONDITIONING AMPLIFIER

B -- PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE
A -- Continue to next step.

2. INSPECT A/C EVAPORATOR TEMPERATURE SENSOR

(a) Remove the A/C evaporator temperature sensor.

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

Standard Resistance:

NOTICE:
* Only hold the sensor at its connector. Touching the sensor may change the resistance value.
* When measuring, the sensor temperature must be the same as the ambient temperature.

HINT
* As the temperature increases, the resistance decrease (See the graph).
* When replacing the A/C evaporator temperature sensor, the attached sub-harness should be replaced along with the sensor.

NG -- REPLACE A/C EVAPORATOR TEMPERATURE SENSOR
OK -- Continue to next step.

3. CHECK HARNESS AND CONNECTOR (A/C AMPLIFIER - A/C EVAPORATOR TEMPERATURE SENSOR)

(a) Disconnect the connector from the air conditioning amplifier.

(b) Disconnect the connector from the A/C evaporator temperature sensor.

NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR

OK -- REPLACE AIR CONDITIONING AMPLIFIER