Pressure Relief Valve In Cap, Checking

WARNING: This page is about a different car, the 2010 Volkswagen Jetta and 2009 Volkswagen Jetta. However, it is still accessible from the selected car via links, so may be relevant.

CAUTION:

Risk of scalding due to hot steam and hot coolant:

When the engine is warm the coolant system is under pressure.
Wear protective goggles and protective clothing to prevent damage to eyes and scalding.
Reduce pressure by covering the coolant expansion tank cap with a cloth and carefully opening.

-- Open the cap on the coolant expansion tank.

-- Install the cap in the adapter V.A.G 1274/9.

-- Clamp the connecting piece V.A.G 1274 B/1 to the adapter V.A.G 1274/9.

-- Connect the connector piece V.A.G 1274 B/1 to the cooling system tester V.A.G 1274 B using the connecting hose.

-- Generate a maximum pressure of 1.6 bar using the cooling system tester -V.A.G 1274 B-.

Pressure relief valve must not open yet.

If the pressure relief valve opens prematurely:

-- Replace the cap.

-- Increase the pressure to above 1.6 bar.

Pressure relief valve must open.

If the pressure relief valve does not open:

-- Replace the cap.