Detection Condition

DTCs P0645 or P1460 indicates excessive current draw is detected on A/C Clutch Relay (ACCR) circuit when PCM grounds the circuit or voltage is not detected on ACCR circuit when circuit is not grounded by PCM.

Wide Open Throttle Air Conditioning Cut-Off (WAC) output is used by PCM to disengage A/C clutch when A/C operation is desirable. Under normal conditions (A/C off), PCM will ground WAC output which opens normally closed A/C clutch relay. When A/C demand switch is on, and A/C cycling switch and A/C high pressure switch contacts are closed, voltage is supplied to A/C clutch relay and to A/C Control Signal (ACCS) circuit. Voltage on ACCS circuit indicates to PCM that A/C is requested. PCM will verify A/C clutch operation is desirable and adjust idle speed as necessary and unground WAC output. This closes normally closed WOT A/C clutch relay and allows voltage to A/C clutch.