DTC P0645: A/C Clutch Relay Circuit: Description

A/C clutch relay voltage is monitored with ignition on, A/C on and battery voltage more than 10 volts. DTC will set in Powertrain Control Module (PCM) when PCM senses an open or short in A/C clutch relay control circuit. Possible causes are: defective A/C clutch relay, control circuit open or shorted to ground, or defective PCM.