Cooling System, Checking For Coolant Leaks

WARNING: This page is about a different car, the 2014 Volkswagen Jetta, 2013 Volkswagen Jetta, 2012 Volkswagen Jetta, and 2011 Volkswagen Jetta. However, it is still accessible from the selected car via links, so may be relevant.

Special tools and workshop equipment required

Cooling System Tester VAG1274B
Cooling System Tester - Adapter VAG1274/8
Cooling System Tester - Adapter VAG1274/9

Test Conditions

Engine at operating temperature.

Perform the Following

WARNING:

Risk of scalding due to hot steam and hot coolant.

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

-- Open the reservoir.

-- Install the Cooling System Tester - Adapter VAG1274/8 in the coolant expansion tank.

Fig 1: Identifying Cooling System Tester V.A.G 1274 Connected To Coolant Reservoir

Courtesy of VOLKSWAGEN GROUP OF AMERICA, INC.

-- Clamp the Cooling System Tester Connecting Piece VAG1274B/1 in the Cooling System Tester - Adapter VAG1274/8.

-- Connect the Cooling System Tester Connecting Piece VAG1274B/1 to the Cooling System Tester VAG1274B using the hose provided.

-- Generate a positive pressure of approximately 1.0 bar (14.5 psi) using hand pump of cooling system tester.

WARNING:

Risk of scalding!

Before disconnecting the Cooling System Tester VAG1274B from the connecting hose or Adapter VAG1274B/1, the existing pressure must always be reduced.
To do this, press the pressure release valve on the Cooling System Tester VAG1274B until the pressure gauge displays >>0<<.

If the pressure drops:

-- Search for leaking areas and repair the malfunction.

Pressure Relief Valve in Cap, Checking

-- Install the cap in the Cooling System Tester - Adapter VAG1274/9.

Fig 2: Connecting Connector Piece V.A.G 1274 B/1 To Cooling System Tester V.A.G 1274 B Using Connecting Hose

Courtesy of VOLKSWAGEN GROUP OF AMERICA, INC.

-- Clamp the Cooling System Tester Connecting Piece VAG1274B/1 in the Cooling System Tester - Adapter VAG1274/9.

-- Connect the Cooling System Tester Connecting Piece VAG1274B/1 to the Cooling System Tester VAG1274B using the hose provided.

-- Actuate the hand pump.

The pressure release valve must open at 1.4 to 1.6 bar (20.30 to 23.20 psi).

If the pressure relief valve opens too early or too late:

-- Replace the cover.