KM - Testing Notes

NOTE: You should enter this Pinpoint Test only when directed here from Diagnostic Routines or Pinpoint Test TA.

REMEMBER: To prevent the replacement of good components, be aware that the following non-Electronic Engine Controls (EEC) areas may be at fault:

- Refrigerant charge

- Ambient temperature less than 7°C (45°F)

This Pinpoint Test is intended to diagnose only the following:

- Harness circuits: Wide Open Throttle A/C Cut-Off (WAC), VPWR, GND, POWER-TO-CLUTCH, AC Demand (ACD)

- WAC relay (11433 or 13A025)

- Powertrain Control Module (PCM) (12A650)

DESCRIPTION:

When the A/C demand switch is turned on and the Low Pressure (LP) switch is closed, the ACD input (Pin 23 or 10) to the PCM is low, indicating that A/C is requested. The PCM will 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.

Air Conditioning Circuit Schematic: