Port Fuel Injection

Chart C-10 - A/C Clutch Control:

Wiring Diagram for A/C Clutch Control:

CHART C-10 A/C CLUTCH CONTROL


Circuit Description:

When an A/C mode is selected on the A/C control switch, ignition voltage is supplied to the compressor low pressure switch. If there is sufficient A/C refrigerant pressure, the low pressure switch will be closed and complete CKT 901 to the closed high pressure cut-off switch and to CKT 459. The voltage on CKT 459 to the ECM is shown by the "Scan" tool as A/C request "ON" (voltage present), "OFF" (no voltage). When a request for A/C is seen by the ECM, the ECM will ground CKT 458 of the A/C clutch control relay, the relay contact will close, and current will flow from CKT 459 to CKT 59 and engage the A/C compressor clutch. A "Scan" tool will show the grounding of CKT 458, as A/C clutch "ON". Also, when voltage is seen by the ECM on CKT 459, the cooling fan will be turned "ON".