Non Turbo Fan Opertion:
Radiator fan operation is control by the Powertrain Control Module (PCM) with inputs from the temperature of the coolant, which is sensed by the coolant temperature sensor, and vehicle speed which is measured by the vehicle speed sensor. The PCM turns on the fan through either the high or low speed fan relay. The PCM provides a ground to the relay's control circuit.
To control radiator fan operation, the PCM looks at inputs from:
? A/C pressure transducer (turbo only)
? Ambient temperature
? Vehicle speed
oil temperature (automatic transmission only)A/C High Pressure Switch Operation:
The A/C high pressure switch is located on the rear of the A/C compressor. The A/C high pressure switch turns off the compressor if the refrigerant system pressure exceeds 3240 kPa (470 psi). The A/C high pressure switch is factory calibrated and cannot be adjusted or repaired and, if faulty or damaged, must be replaced.A/C Low Pressure Switch Operation:
The A/C low pressure switch is electrically connected in series with the A/C-heater control mode switch and the A/C high pressure switch, between ground and the powertrain control module (PCM). The A/C low pressure switch contact opens or closes the path the ground, signaling the PCM to turn the A/C compressor clutch
on and off. This regulates the refrigerant system pressure and controls evaporator coil temperature. Controlling the evaporator temperature prevents condensate water on the evaporator fins from freezing and obstructing air conditioning system air flow.
The A/C low pressure switch contacts are open when the suction pressure is approximately 152 kPa (22 psi) or lower. The switch contacts will close when the suction pressure rises to approximately 234 to 262 kPa (34 to 38 psi) or above. Lower ambient temperatures, below approximately -1° C (30° F), will also cause the switch contacts to open. This is due to the pressure/temperature relationship of the refrigerant in the system
It could be the temp sensor for this,