Pressure leak test (VW Passat B6)

Contents: Preliminary pumping ↓ Pumping (main) ↓ Additional pumping ↓

To carry out the check it is necessary that the brake system, its functionality and tightness (hydraulic unit, brake hoses, brake lines and brake calipers) should be fine.

Unscrew the bleeder screw for bleeding one of the front brake calipers. Connect the pressure gauge and bleed.

Apply pressure to the brake pedal until the pressure gauge shows an excess pressure of 50 bar. During the test, the pressure drop should not exceed 4 bar for 45 minutes. If the pressure drop is greater, replace the master brake cylinder.

Note: Brake fluid is poisonous. Do not allow brake fluid to come into contact with paintwork as this will damage it.

Note: Brake fluid is hygroscopic – it attracts moisture from the surrounding air. Brake fluid may only be stored in closed containers.

Note: If drops of brake fluid are found, rinse with plenty of water.

Note: To bleed the hydraulic unit, it is necessary to create a pressure of at least 2 bar.

Preliminary pumping

Connect the device for filling and bleeding the brake system or.

Pumping sequence:

1 - Bleed the front right and left calipers simultaneously
2 - Bleed the rear left and right brake calipers simultaneously

The bleed nipples with the attached bleed tank hoses must remain open until the fluid starts to flow out without bubbles.

Then, using the "Basic setting" function, bleed the hydraulic unit again using the tester.

Pumping (main)

Strictly follow the procedure for bleeding the brake system.

(The article is posted on this website: www.vwmanual.ru)

Connect the device for filling and bleeding the brake system.

Open the bleed nipples in the prescribed sequence and bleed the brake calipers.

1 - Front left brake caliper.
2 - Front right brake caliper.
3 - Rear left brake caliper.
4 - Rear right brake caliper.

Use a suitable bleed hose. It must fit tightly on the bleed nipple to prevent air from entering the brake system.

The brake caliper bleeder nipple with the container hose attached must remain open until fluid begins to flow out without bubbles.

Additional pumping

Press the brake pedal firmly and do not release it.

Note: An assistant is required to complete this task.

Open the brake caliper bleeder screw.

Press the brake pedal all the way down.

Close the nipple without releasing the brake pedal pressed all the way down.

Slowly release the brake pedal.

This bleeding process should be repeated 5 times for each brake caliper.

Pumping sequence.