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Home >> Volkswagen >> 2021 >> ID.4 Pro, AWD >> Repair and Diagnosis >> External Pages >> Different car >> Section 102 (Cooling System) >> 19 Cooling System >> Cooling System/Coolant >> Cooling System, Checking For Leaks >> Check The Cooling System For Leaks
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Check The Cooling System For Leaks

WARNING: This page is about a different car, the 2023 Volkswagen ID.4. However, it is still accessible from the selected car via links, so may be relevant.

Condition

CAUTION:

The cooling system can be under pressure. Risk of scalding by hot steam and hot coolant.

Possibility of scalding the skin and other parts of the body.

- Wear safety gloves.

- Wear protective eyewear.

- Reduce the pressure: cover the coolant expansion tank cap with a suitable towel and carefully open.

-- Open the caps -arrow-.

GWWN19-11536Courtesy of VOLKSWAGEN GROUP OF AMERICA, INC.

-- Screw the Adapter:VAS 691 005/5  -1- on the coolant expansion tank -2-.

GWWN19-11632Courtesy of VOLKSWAGEN GROUP OF AMERICA, INC.

-- Connect the Cooling System Tester:V.A.G 1274B  -3- to the adapter -1-.

-- Operate the hand pump multiple times and create a pressure of 1.5 bar (21.76 psi).

Condition

-- If the pressure falls more than 0.2 bar (2.9 psi), search for leaks and correct the problem.

Tip

The pressure loss of 0.2 bar (2.9 psi) within 10 minutes is due to the cooling of the coolant. If the temperature of the coolant is equal to the ambient temperature, no loss of pressure is permitted.

Condition

-- Drain the pressure from the cooling system tester and from the coolant expansion tank.

-- Open the cap.