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Notes on installing air conditioner compressor, engine code BAD > < Tasks of receiver with dryer bag

Golf Mk4

Checking air conditioning system pressure switchF129
Checking air conditioning system pressure switch -F129-
t  Some vehicles are equipped with a high pressure sensor -G65- instead of an air conditioner pressure switch -F129-.
t  The pressure switch can be removed without extracting the refrigerant from the refrigerant circuit.
t  Visual check: ensure that O-ring 10.8 mm x 1.8 mm is seated in groove.
   
Switch part between chamber 1 and chamber 2 of connector housing switches air conditioning system magnetic coupling -N25- off when refrigerant circuit is insufficiently filled or pressure is too high:
–  Opens below 1.2 bar and closes again above 2.4 bar (switching threshold)
–  Opens above 32 bar and closes again below 24 bar (switching threshold)
Checking switch part:
–  Briefly bridge circuit between chambers 1 and 2 with engine running. The refrigerant circuit is empty if the air conditioner magnetic coupling -N25- switches on.
  V87-1360
The switch part between chamber 3 and chamber 4 of the connector housing switches the radiator fan -V7- to the second speed via radiator fan control unit -J293- when the pressure in the refrigerant circuit rises.
–  Closes above 16 bar and opens below 12.5 bar (switching threshold)
Evaluating checks of air conditioning system pressure switch -F129-
t  The following tests are performed with component installed.
  V87-1360
To assess the air conditioner's performance, perform and evaluate the following checks:
–  Check the air conditioner's charging level; the air-conditioner is switched off if the pressure is too low (for example, loss of refrigerant).
–  Check blower switch-on; radiator fan -V7- is switched to the next higher speed when the pressure in the refrigerant circuit rises (excessive pressure).
–  Check air conditioner switch-off; the air conditioner is switched off when pressure is excessive (for example when engine cooling is insufficient).
  V87-1360

Notes on installing air conditioner compressor, engine code BAD > < Tasks of receiver with dryer bag