A/C Refrigerant High Pressure Switch -F23-
Note
For switching pressures, removing and installing switches and switch arrangement and version, see vehicle-specific refrigerant circuit.
Function:
Switches the coolant fan to the next higher level when the pressure in the refrigerant circuit increases (approximately 16 bar (232 psi) ).
Magnetic Clutch High Pressure Switch -F118-
Note
For switching pressures, removing and installing switches and switch arrangement and version, see vehicle-specific refrigerant circuit.
Function:
Switches off A/C compressor when there is excessive pressure in the refrigerant circuit (approximately 32 bar (464 psi) ).
A/C Refrigerant Low Pressure Switch -F73-
Note
For switching pressures, removing and installing switches and switch arrangement and version, see vehicle-specific refrigerant circuit.
Function:
Switches off A/C compressor when there is excessive pressure in the refrigerant circuit (approximately 2 bar (29 psi) ).
Refrigerant Circuit Connections with Valve for Switches
Note
For switching pressures, removing and installing switches and switch arrangement and version, see vehicle-specific refrigerant circuit.
WARNING
There is a danger of ice-up.
Refrigerant will leak out if refrigerant circuit is not discharged.
Refrigerant must be extracted before removing valve -C-. If refrigerant circuit is not opened within 10 minutes of extraction, pressure may form in refrigerant circuit due to evaporation. Extract the refrigerant once more.
A/C Pressure Switch -F129-
Note
For switching pressures, removing and installing switches and switch arrangement and version, see vehicle-specific refrigerant circuit.
This pressure switch has 3 functions:
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-.
High Pressure Sensor -G65-
Note
For switching pressures, removing and installing switches and switch arrangement and version, see vehicle-specific refrigerant circuit.
This High Pressure Sensor -G65- is installed in place of an A/C Pressure Switch -F129-.
The high-pressure sensor generates a square-wave signal or a data telegram when voltage is applied. This signal changes along with pressure in the system.
The downstream control modules (coolant fan control module, ECM), Front A/C Display Control Head -E87- or Climatronic Control Module -J255-, etc.) use this signal to calculate pressure in the refrigerant circuit and to activate the coolant fans and motor and A/C Clutch -N25- or to change the A/C Compressor Regulator Valve -N280- activation.
A/C Pressure/Temperature Sensor -G395-
Note
For switching pressures, removing and installing switches and switch arrangement and version, see vehicle-specific refrigerant circuit.
WARNING
There is a danger of ice-up.
Refrigerant will leak out if refrigerant circuit is not discharged.
The refrigerant must be extracted before the A/C Pressure/Temperature Sensor -G395- is removed. If refrigerant circuit is not opened within 10 minutes of extraction, pressure may form in refrigerant circuit due to evaporation. Extract the refrigerant once more.
This A/C Pressure/Temperature Sensor -G395- is installed instead of the High Pressure Sensor -G65- or A/C Pressure Switch -F129-.
The pressure signal is always being checked, where the temperature signal is only checked at temperatures above 0 ºC (32 ºF).
The Climatronic Control Module -J255- operates with this information and controls the coolant fans and activation of the A/C Compressor Regulator Valve -N280-.
A/C Compressor Regulator Valve -N280-
Note
For switching pressures, removing and installing switches and switch arrangement and version, see vehicle-specific refrigerant circuit.
The regulator valve is implemented into the compressor. It is activated by the A/C Display Control Head -E87- or Climatronic Control Module -J255-. Pressure on the low pressure side is influenced via the regulator valve and thus regulates the temperature in the evaporator.
Note
The A/C Compressor Regulator Valve -N280- is a component of the A/C compressor and cannot be replaced separately.
Volkswagen Tiguan Service and Repair Manual > Refrigerant R134a Servicing: Refrigerant Circuit, Detecting Leaks
Searching for Refrigerant Circuit Leaks with Compressed Air or Nitrogen
Note
This repair manual describes different methods for detecting leaks in
the refrigerant circuit. These methods have been tested and result in
success when used correctly.
If when searching for compressed air / Nitrogen ...