KM - Testing Notes

NOTE: You should enter this Pinpoint Test only when you have been directed here from Quick Test or Pinpoint Test TA.



REMEMBER



To prevent the replacement of good components, be aware that the following non-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: WAC, VPWR, GND, POWER-TO-CLUTCH, ACD

- WAC relay

- Processor assembly



DESCRIPTION

A/C Cutout Switch:

WAC

When the A/C demand switch is turned on and the Cyclic Pressure switch/Low Pressure Switch is closed, voltage passes through the normally closed WAC relay to the A/C clutch. Under certain conditions the EEC-IV processor can interrupt this voltage, turning off the A/C. To do this, the EEC-IV processor will ground the WAC output (Pin 54), which will energize the coil in the WAC relay. This will result in the normally closed contacts opening, interrupting the voltage supply to the A/C clutch


ACC/S

The EEC-IV processor uses the ACC/S input to determine when the A/C demand switch is on and the Cyclic Pressure switch/Low Pressure (LP) switch is closed. This information is used primarily for idle control.