Evaporator Temperature Sensor Circuit - Air Conditioning System

AIR CONDITIONING: AIR CONDITIONING SYSTEM: 13: Evaporator Temperature Sensor Circuit

DTC 13 - Evaporator Temperature Sensor Circuit

DESCRIPTION

This sensor detects the temperature inside the cooling unit and sends appropriate signals to the A/C amplifier.





WIRING DIAGRAM





INSPECTION PROCEDURE

PROCEDURE

1. INSPECT AIR CONDITIONING AMPLIFIER (TE, SG)




(a) Remove the A/C amplifier with the connectors still connected.
(b) Turn the ignition switch ON.
(c) Measure the voltage according to the value(s) in the table below.
Standard voltage:





OK -- PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE

NG -- Continue to next step.

2. INSPECT COOLER THERMISTOR NO. 1 (EVAPORATOR TEMPERATURE SENSOR)




(a) Remove the cooler thermistor No. 1 (evaporator temp. sensor).




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





- Even slightly touching the sensor may change the resistance value. Be sure to hold the connector of the sensor.
- When measuring the sensor temperature, it must be the same as the ambient temperature.

HINT: As the temperature increases, the resistance decreases (see the graph).

NG -- REPLACE COOLER THERMISTOR NO. 1 (EVAPORATOR TEMPERATURE SENSOR)
OK -- Continue to next step.

3. CHECK HARNESS AND CONNECTOR (COOLER THERMISTOR NO. 1 - A/C AMPLIFIER)
(a) Check for open and short in the harness and the connector between the cooler thermistor No. 1 (evaporator temp. sensor) and the A/C amplifier Electronic Circuit Inspection Procedure.

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

4. CHECK DTC
(a) Start up the DTC check mode.
(b) Check that DTC 13 is not output again.
Result:





B -- SYSTEM IS OK
A -- REPLACE AIR CONDITIONING AMPLIFIER