If the coolant expansion tank is filled with coolant due to the vacuum, the coolant expansion tank must be drained:

WARNING: This page is about a different car, the 2023 Volkswagen Atlas. However, it is still accessible from the selected car via links, so may be relevant.

-- 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 .

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-- 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:VAS 6096 and Cooling System Tester - Directional Valve:VAS 691 005/5 and remove the Hose Clamps - Up To 25mm:3094 .

-- Switch on the Electric Vacuum Pump and extract again for five minutes.

If the coolant expansion tank is no longer filled with coolant:

-- Close the valve -B- and switch off the Cooling System Charge Kit - Electric Vacuum Pump:VAS 6096/2 .

-- Watch the pressure gauge. The needle of the pressure gauge must not move.

-- >>Slowly<< open the shut-off valve -A-, to prevent the foaming up of the coolant.

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Coolant is extracted from the Cooling System Charge Kit:VAS 6968 container by pressure in the coolant system and the system is filled.

-- Close after filling the shut-off valve -A-.

-- Remove the Cooling System Charge Kit - Electric Vacuum Pump:VAS 6096/2 , Cooling System Charge Kit:VAS 6096 and Cooling System Tester - Directional Valve:VAS 691 005/5 from the coolant expansion tank.

-- Fill the coolant up to the weld seam -arrow- and seal the coolant expansion tank.

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NOTE:

The elevated coolant level is necessary because the coolant level will still decrease due to the ventilation process.

-- Install the noise insulation. Refer to OVERVIEW - NOISE INSULATION .

-- If the vehicle has a parking heater, switch it on for about 30 seconds.

-- Set the temperature to "HI".

-- Press AC to turn off the A/C compressor.

The LED in the button must not come on.

-- Let the engine run in idle until the radiator fan switches on.

-- Switch off the engine and use the Vehicle Diagnostic Tester to check the engine control module DTC memory. If necessary, erase the DTC memory.

NOTE:

The electric coolant pump may store an error in the engine control module due to an air bubble in the cooling system. This air bubble is pushed out after the first start.