High Pressure Sensor, Function

High Pressure Sensor, Function

Where equipped, the High Pressure Sensor (G65) transmits a square wave signal to Coolant Fan Control (FC) Module (J293) at a rate which varies according to the refrigerant system pressure.

The signal from High Pressure Sensor (G65) is processed as follows:

Based on the pulse rate transmitted by the High Pressure Sensor (G65) , the Coolant Fan Control (FC) Module (J293) determines the A/C refrigerant system pressure and controls the function of the A/C Clutch (N25) and Coolant Fans accordingly. For example:

• Switches the Coolant Fan (V7) to the next higher speed when pressure in the refrigerant circuit increases.

• Switches off A/C Clutch (N25) when pressure is excessive (for example when engine cooling is insufficient).

• Switches off A/C Clutch (N25) off when pressure is too low (for example with low/no refrigerant).

The signal generated by High Pressure Sensor (G65 ) is also provided as an input to the Motronic Engine Control Module (ECM). As the amount of torque needed to drive the A/C compressor varies according to the refrigerant system pressure, the ECM processes this signal in order to enhance engine performance.