A/C refrigerant system, valves and switches: Functions:
WARNING: This page does not describe the selected car, but rather 27 other vehicles, including the 2002 Volkswagen Cabrio, 2001 Volkswagen Cabrio, 2000 Volkswagen Cabrio, 1999 Volkswagen Jetta, and 1999 Volkswagen Golf. However, it is still accessible from the selected car via links, so may be relevant.
Switches the A/C clutch -N25- OFF if system pressure is too low (low refrigerant charge). For this function, switching takes place between terminal 1 (T4a/1) and terminal 2 (T4a/2).
- Switch opens (compressor OFF): below 1.2 bar (17.4 psi)
- Switch closes (compressor ON): above 2.4 bar (34.8 psi)
Switches A/C clutch -N25- OFF if system pressure is too high. For this function, switching takes place between terminal 1 (T4a/1) and terminal 2 (T4a/2).
- Switch opens (compressor OFF): above 32.0 bar (464 psi)
- Switch closes (compressor ON): below 24.0 bar (348 psi)
Switches the radiator coolant fan -V7- to second speed when A/C system pressure increases. For this function, switching takes place between terminal 3 (T4a/3) and terminal 4 (T4a/4).
- Switch closes (2nd speed ON): above 16.0 bar (232 psi)
- Switch opens (2nd speed OFF): below 12.5 bar (181 psi)