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Computerized Output

A/C Control Circuit Diagram (Electronic And Dual Zone A/C):





ELECTRONIC AND DUAL ZONE A/C

A/C Control Circuit Diagram (Manual A/C):





MANUAL A/C


The PCM controls the A/C compressor clutch relay. The relay gets battery power when the ignition is turned "ON" and energizes when the PCM completes the circuit to ground. When the A/C is turned on, the PCM delays the clutch engagement of the A/C compressor to allow the IAC valve to raise the engine idle speed to compensate for the added load. The PCM also causes the relay to disengage the A/C clutch at wide open throttle, when the engine is overheating, and when the A/C system pressures are not within a specified range.