A/C System - Manual

The A/C Heater System's A/C Control Assembly houses the A/C Switch and Blower Control. With the Ignition Switch in the RUN or START position, the [1][2]Blower Motor Relay is energized through the interior COOLING FAN fuse (15A) and closes it contacts, applying a battery voltage through the main HEATER fuse (40A) to the Blower Motor. Placing the Blower Motor Selector Switch in any of its four operating modes supplies a ground for the circuit and engages the Blower Motor.

For LX, closing the A/C Switch of the A/C Control Assembly supplies a ground to the [1][2]A/C Relay.

Refrigerant Pressure Switch

If the Refrigerant Pressure Switch is closed, current through the AIR COND fuse (20A) will be applied to the Compressor Clutch via the Integrated Relay Control Module, and the Compressor will spin. In the event of decreasing temperature, the Refrigerant Pressure Switch opens and removes the current applied to the Compressor Clutch, causing the Compressor to stop spinning. Without Compressor operation the refrigerant temperature slowly rises until the Refrigerant Pressure Switch closes, starting Compressor to spin.

For GL, the Refrigerant Pressure Switch differs from LX in that it receives a ground from the Electronic Control Assembly (ECA). In addition, the ECA provides a ground for the Condenser Fan Relay. Therefore, with the A/C Switch in the ON position, the Condenser Fan Relay is energized by the AIR COND fuse (20A). Upon closing its contacts, current is supplied to both the Condenser Fan Motor and Compressor Clutch. When the refrigerant temperature drops below a certain value during A/C operation, the Refrigerant Pressure Switch opens and removes the ground signal from the ECA. The ECA removes the ground from the Condenser Fan Relay, opening its contacts and causing the Condenser Fan Motor and the Compressor to stop spinning. Without Compressor Operation, the refrigerant temperature slowly rises until the Refrigerant Pressure Switch closes, causing the Compressor and the Condenser Fan Motor to spin.