Possible causes
– Faulty A/C Evaporator Temperature Sensor
– A/C Evaporator Temperature Sensor harness is open or shorted
– A/C Evaporator Temperature Sensor circuit poor electrical connection
– A/C Evaporator Temperature Sensor harness is open or shorted
– A/C Evaporator Temperature Sensor circuit poor electrical connection
When is the obd code mean?
When the A/C Evaporator Temperature (ACET) sensor signal is intermittent the Powertrain Control Module (PCM) will triggered the P0539 code.
Symptoms
– Engine Light ON (or Service Engine Soon Warning Light)
– A/C Inoperative
– A/C Blows Warm
– A/C Inoperative
– A/C Blows Warm
P0539 FORD OBD Code Description
The Powertrain Control Module (PCM) sources a low current 5 volts on the A/C Evaporator Temperature (ACET) sensor circuit. As the A/C evaporator air temperature changes, the ACET circuit resistance changes (which changes the voltage the PCM detects).