High Pressure Sensor G65

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Fig 1: High Pressure Sensor - G65

Courtesy of VOLKSWAGEN UNITED STATES, INC.

The High Pressure Sensor G65 is installed instead of the A/C Pressure Switch F129 or the A/C Pressure/temperature Sensor G395.

The A/C Pressure/temperature Sensor G395 ( "grey" housing at present) and the High Pressure Sensor G65 ( "black" housing at present) currently only differ in terms of housing color and attention is therefore to be paid to correct assignment on replacement (part number → Electronic Parts Catalog ETKA ). As these two sensors emit different signals, the relevant control module can only evaluate the signal to which it has been matched.

The High Pressure Sensor G65 generates a square-wave signal or data telegram when voltage is applied. This signal changes with the pressure in the system.

The downstream control modules (coolant fan control module, Engine Control Module (ECM), A/C Control Head E87 , Climatronic Control Module J255 etc.) use this signal to calculate the pressure in the refrigerant circuit and to actuate the coolant fans, fan motor and A/C Clutch N25 accordingly or to modify actuation of the A/C Compressor Regulator Valve N280.