KM - Testing Notes

A/C Circuit Schematic:

When the A/C demand switch is turned on and the Low Pressure (LP) switch is closed, the ACD input (Pin 23) to the Powertrain Control Module (PCM) is low, indicating that A/C is requested. The PCM will then ground the A/C ON output (Pin 54) which will energize the coil in the A/C relay. This will close the normally open contacts, sending B(+) voltage to the A/C Clutch. The PCM will also adjust idle as necessary.