Connecting For Measuring And Testing, One Service Connection
Special tools and workshop equipment required
- Valve Adapters V.A.G 1785/9
- V.A.G 1785/10 or Air Conditioning Adapter Set V.A.G 1786
- Work procedure may vary depending on the type of tools selected (the tool-specific operating instructions should therefore be followed).
The work procedure is always to be performed as described in the operating instructions for the A/C service station.
The charging hoses are to be connected as follows to prevent the entry of air or moisture into the refrigerant circuit:
-- Switch off the ignition.
-- Connect service station to power supply.
-- Remove the caps from the service connections or connections with valve (refer to vehicle-specific refrigerant circuit). Refer to Removal and Installation (vehicle-specific repair information).
-- Evacuate charging hoses if necessary.
-- Connect quick-release coupling to service connection of refrigerant circuit.
- Never open valves on low or high-pressure side with engine running. Otherwise, compressor or service station could be destroyed by a short circuit between high and low-pressure sides of refrigerant circuit if air conditioning system is switched on.
-- Only tighten the handwheel in the quick-release coupling just enough so the service connection is open. Watch the pressure gauge and do not place too much pressure on the valve.
-- Start the engine and perform the planned tests and measurements.
-- Compare values determined to specified measured values. Refer to PRESSURES, CHECKING .
-- Before disconnecting quick-release coupling, close it by screwing out handwheel.
Vehicles with only one service connection
Screw V.A.G 1785/9, V.A.G 1785/10 or V.A.G 1786 to refrigerant circuit connections with valve and bleed charging hoses during connection to adapters (faintly audible escape of refrigerant gas is permitted).
-- The charging hose must be installed with a valve opener for opening valve in valve adapter.