Troubleshooting

Evaporator Temperature Sensor (Part 1 Of 2):

Evaporator Temperature Sensor (Part 2 Of 2):

Self-diagnosis indicator light D comes on: A problem in the evaporator temperature sensor circuit.

The evaporator temperature sensor is a temperature dependent resistor (thermistor). The resistance of the thermistor decreases as the evaporator outlet air temperature increases.

CAUTION: The sensor uses a thermistor which can be damaged if high current is applied during testing. Therefore, use a circuit tester with an output of 1 mA or less at the 20 K Ohms range.