Circuit Description

HVAC

How the Climate Control Circuit Works
The climate control unit controls the blower controls, air delivery, and A/C compressor controls either automatically or semi-automatically. The control unit receives battery voltage at all times through fuse 56. With the ignition switch in ON (II), battery voltage is supplied through fuse 3. The control unit is grounded at G402.

A/C Pressure Switch
The A/C pressure switch is located in the condenser outlet line where refrigerant is in a high temperature/high pressure liquid state. The switch will sense abnormally high or low pressure, and open the circuit. This removes ground from the PCM, and turns off the compressor.