Possible causes

– Faulty Evaporator Temperature sensor
– A/C evaporator temperature sensor harness is open or short
– A/C evaporator temperature sensor circuit poor electrical connection

When is the code detected?

The Powertrain Control Moduel (PCM) has detected a fault in the temperature sensor circuit

Symptoms

– Engine Light ON (or Service Engine Soon Warning Light)
– A/C Inoperative
– A/C Blows Warm

P0535 FORD Description

The refrigerant system incorporates an A/C compressor controlled by the Powertrain Control Moduel (PCM) through an A/C clutch relay. The climate control assembly sends an A/C request signal to the instrument cluster module, which relays the request to the PCM. An evaporator discharge air temperature sensor is used to disengage the A/C compressor clutch when the evaporator core temperature falls below an acceptable temperature.

The 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).