F 150 2WD Pickup V8-351 5.8L Lightning (1993)
A/C Clutch Signal: Description and Operation
PURPOSE
The A/C signal is an input to the Powertrain Control Module (PCM) which informs it that the A/C clutch has been energized. The PCM adjusts
the idle speed and air/fuel mixture to compensate for the increased engine load.
OPERATION
With the A/C demand switch closed and both the cycling pressure switch and the high pressure cutout switch shut, battery voltage will be supplied
to circuit ACC (10) informing the PCM the A/C clutch is energized.
RELATED DIAGNOSTIC TROUBLE CODES
DTC 539 - A/C request during self test procedure.
DTC 559 - A/C ON circuit failure.
