Circuit Description

PCM uses input signal from A/C refrigerant pressure sensor to determine if it should turn on engine coolant fans. When signal is out of range, DTC will set and PCM will not allow A/C clutch to engage.

Conditions required to set DTC are:

• Engine is running.
• System voltage is greater than 10 volts.
• A/C is requested.
• A/C refrigerant pressure sensor signal less than 0.1 volt.

Or

• A/C refrigerant pressure sensor signal greater than 4.9 volts.
• Either condition present longer than 20 seconds.