Operation CHARM: Car repair manuals for everyone.

Pressure Sensor



Pressure Sensor

The pressure sensor is an essential instrument in assessing the air conditioning system. It detects the current pressure in the system and supplies a PWM signal (Pulse Width Modulation) to the a/c control unit. The a/c control unit relays this signal to the CAN bus for further use.

This PWM signal is employed for the purposes of:
- Low-pressure shut-down (p < 29 psi/2 bar)
- High-pressure shut-down (p > 406 psi/28 bar)
- Condenser cooling (see also section "Condenser fan")

The following components serve as actuators:
- Drive motor for temperature mix flap
- Drive motor for central distributor flap
- Drive motor for defrost/footwell distributor flap
- Drive motor for fresh air/recirc. air distributor flap
- PWM - fan motor voltage