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Home >> Volkswagen >> 2021 >> ID.4 Pro, AWD >> Repair and Diagnosis >> Engine Mechanical >> Cooling Fan >> Cooling System >> 19 Cooling System >> Cooling System/Coolant >> Coolant Concentration, Checking
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Coolant Concentration, Checking

Special tools and workshop equipment required 

Tip

Checking the coolant concentration is necessary to determine if there is air in the cooling system. If there is air in the cooling system, the cooling system may inadmissibly lower during running time. Overheating of the motor is also possible.

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 coolant expansion tank cap -arrow-.

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

-- Check the coolant level, it must be approximately 10 mm above the MAX mark or directly at the MAX mark -1-. Fill the coolant if necessary.

GWWN19-11600Courtesy of VOLKSWAGEN GROUP OF AMERICA, INC.

-- Position the Cooling System Tester: V.A.G 1274 B  -3- with the Test Adapter: VAS 691 005/5  -1- onto the coolant expansion tank -2-.

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

-- Generate pressure of 1.5 bar (21.76 psi) using the cooling system tester hand pump.

-- Monitor the coolant level in the expansion tank.

If the coolant level in the expansion tank lowers by more than 20 mm, this indicates an air bubble in the cooling system.

-- Perform the "Cooling System, Bleeding" function using the Vehicle Diagnostic Tester. Refer to Diagnostic Entries .

-- Repeat checking the coolant concentration.

If the coolant level in the expansion tank lowers by less than 20 mm, then it is filled correctly.

Continuation

-- Release the pressure at the cooling system tester hand pump -3-.

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

-- Remove the adapter -1- from the coolant expansion tank.