A4 Cabriolet L4-1.8L Turbo (AMB) (2005)
High Pressure Sensor / Switch: Description and Operation
A/C Pressure Switch F129
Refrigerant Circuit Switches And Sensors And Related Connections
NOTE: Refer to vehicle-specific refrigerant circuit for switching pressures, switch removal/installation and switch layout/design Heating, air
conditioning or Air conditioning.
A/C Pressure Switch F129
This pressure switch has 3 functions:
1. Switches coolant fan up to next speed setting in the event of pressure increase (approx. 16 bar) in refrigerant circuit.
2. Switches off air conditioner in the event of excessive pressure (approx. 32 bar) caused for example by inadequate engine cooling.
3. Switches off air conditioner in the event of insufficient pressure (approx. 2 bar) caused for example by loss of refrigerant.
NOTE: The A/C Pressure Switch F129 replaces the A/C Refrigerant High Pressure Switch F23, the A/C Refrigerant Low Pressure Switch F73
and the A/C Refrigerant High Pressure Switch F118.