Compressor Clutch Relay: Description and Operation

Wiring Diagram For A/C Clutch Circuit:

When the Electronic Climate Control (ECC) head is switched to the "ON" position and the A/C system has adequate charge, an A/C request signal is sent to the ECM. When the A/C request signal is received by the ECM, the ECM will delay grounding relay circuit 459 long enough to adjust idle speed. Once the idle speed has been adjusted, the ECM will ground the relay circuit 459 which will allow current to flow to the A/C clutch. The ECM will also disable the A/C clutch relay during Wide Open Throttle (WOT).