A/C Pressure Switch -F129-

WARNING: This page is about a different car, the 2021 Audi S4 and 2021 Audi A4 Quattro. However, it is still accessible from the selected car via links, so may be relevant.

NOTE:

Switch pressures, removing and installing switches as well as switch arrangement and version. Refer to vehicle specific refrigerant circuit. Refer to Refrigerant Circuit .

This pressure switch has 3 functions:

Fig 1: A/C Pressure Switch - F129

Courtesy of AUDI OF AMERICA, LLC

1. Switches the coolant fan to the next higher level when the pressure in the refrigerant circuit increases (approximately 16 bar (232 psi)).

2. Switches off A/C system if pressure is excessive (approximately 32 bar (464 psi)), for example because of insufficient engine cooling.

3. Switches off A/C system if pressure is insufficient (approximately 2 bar (29 psi)), for example loss of refrigerant.

NOTE:

A/C Pressure Switch -F129- replaces the A/C Refrigerant High Pressure Switch -F23-, A/C Refrigerant Low Pressure Switch -F73- and the Magnetic Clutch High Pressure Switch -F118-.