Checking the Pressure Relief Valve in the Version 1 Cap

Fig 1: Coolant Expansion Tank

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-- Position the Cooling System Tester: VAG1274B  with the Adapter : VAG1274B/15  on the cap.

-- Generate approximately 2 bar (29.01 psi) pressure using the cooling system tester hand pump.

Fig 2: Identifying VAG1274B & VAG1274B/15

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• The pressure must lower to 1.8 to 1.6 bar (26.11 to 23.21 psi) and stay there.

-- If the pressure relief valve does not react as specified, replace the cap.

Checking the Pressure Relief Valve in the Version 2 Cap:

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-- Position the Cooling System Tester: VAG1274B  with the Cooling System Tester - Adapter: VAG1274/9  on the cap -1-.

Fig 3: Identifying VAG1274B & VAG1274/9

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• The pressure release valve must open at 1.6 to 1.8 bar (23.21 to 26.11 psi).

-- If the pressure relief valve does not react as specified, replace the cap.