Manual Climate Controls

The compressor for the air conditioning system is belt-driven by the engine through the A/C Compressor Clutch. The Powertrain Control Module (PCM) controls the A/C Compressor depending on the HVAC Programmer Module mode and temperature settings. The PCM controls the A/C Compressor Clutch by activating the A/C CLU micro relay 34.

When the PCM receives a A/C request from the HVAC Programmer Module through circuit 762, it activates the A/C CLU micro relay 34 through circuit 459. The battery voltage is applied from the A/C mini fuse 24 and A/C micro relay 34 to the A/C Compressor Clutch through circuit 59. Circuit 59 also carries the A/C Compressor status to the PCM. The A/C Diode prevents current flow that could damage A/C Compressor Clutch components. The A/C Compressor Clutch is grounded through circuit 150 to Splice Pack #100, SP100.

The PCM uses the A/C Refrigerant Pressure Sensor to control refrigerant pressure. If the refrigerant pressure is too high (i.e., could cause engine overheating), the PCM disengages the A/C Compressor Clutch. The A/C Refrigerant Pressure Sensor sends refrigerant pressure data to the PCM through circuit 380. Circuit 407 supplies the A/C Refrigerant Pressure Sensor with ground voltage, and circuit 474 supplies 5V reference voltage.