Cooling System, Checking For Leaks: Procedure

2016 Volkswagen Jetta Hybrid SEL PremiumSECTION Procedure
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NOTE:

To perform the leak test correctly, a check (self-test) of the :VAG1274B  must be performed first.

Check (Self-Test) of :VAG1274B 

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-- Operate the :VAG1274B  multiple times.

-- Create a pressure of 3.0 bar (43.5 psi) on the :VAG1274B  .

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-- Observe the pressure on the pressure gauge of the :VAG1274B  for 30 seconds.

If No Pressure is Built or the Pressure Decreases:

The :VAG1274B  is leaking and must not be used.

Cooling System, Checking for Leaks

CAUTION:

The cooling system is under pressure when the engine is warm. Risk of scalding due to hot steam and hot coolant.

Scalding the skin and other parts of the body is possible.

- Wear safety gloves.

- Wear protective eyewear.

- Reduce the pressure by covering the coolant expansion tank cap with a cloth and carefully opening it.

-- Carefully open the cap -1- on the coolant expansion tank -2- in the direction of -arrow-.

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  • Engine at operating temperature.

-- Position the :VAG1274B  with the :VAG1274/8  on the coolant expansion tank.

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

-- If the pressure falls, search for leaks and correct the malfunction.

RENDER: 1.0x

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • You smell fuel, burning insulation, or see smoke.
  • Brakes feel soft, pull hard to one side, or make grinding noises.
  • The engine overheats, stalls repeatedly, or misfires under load.
  • You are missing required tools, torque specs, or safe lifting equipment.
  • You are not confident in the next step or safety outcome.