When the water separator in the is filled with coolant, the coolant expansion tank must be extracted:

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-- Close the shut-off valve -B- and switch off the Electric Vacuum Pump.

-- Seal the supply hose -2- and the return hose -1- of the coolant expansion tank using the Hose Clamps - Up To 25mm :3094  .

-- Remove the connector coupling -arrow- and open the shut-off valve -B- the coolant expansion tank is vented with this.

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-- Remove the Cooling System Charge Kit :VAS 6096  and Cooling System Tester - Directional Valve :VAS 691 005/5  .

-- Extract the coolant from the coolant expansion tank.

-- Reinstall the Cooling System Charge Kit and Test Adapter and remove the hose clamp.

-- Switch on the Electric Vacuum Pump and extract again.