A4 Quattro Cabriolet V6-3.2L (BKH) (2007)
Control Module HVAC: Component Tests and General Diagnostics
High Pressure Sensor Pressure Signal
High Pressure Sensor Pressure Signal
- A - Refrigerant system pressure, high pressure side in bar (absolute pressure)
- B - Signal ratio of square wave signal
- C - Characteristic curve
‹› The Climatronic control module (J255) A/C control head switches the compressor on at a duty cycle greater than 12% (equivalent to an absolute
pressure of approx. 1.8 bar) and less than 87.5% (equivalent to an absolute pressure of approx. 32 bar) if no compressor shutoff condition is
present (by activating the A/C compressor regulator valve (N280).
‹› The compressor is not switched on if the duty cycle is smaller than 12 % or greater than 87.5% (A/C Compressor Regulator Valve (N280) is not
activated).
‹› The duty cycle and pressure calculated by the Climatronic control module (J255) A/C control head are indicated in the measured value block
(display group "001")
‹› In terms of absolute pressure, 0 bar corresponds to an absolute vacuum. Normal ambient pressure equals approximately 1 bar absolute pressure.
On the scales of most pressure gauges, 0 bar corresponds to an absolute pressure of one bar (can be seen from -1 mark below 0).