Bleeding brake hydraulic system
Special tools and workshop equipment required
- Brake Filler And Bleeder Unit:VAS5234
Brake fluid is poisonous.
- It must never be extracted using suction by mouth through a hose.
- If brake fluid contacts skin or eyes, flush or wash adequately to prevent irritation. Get medical attention if necessary.
- It must be disposed of properly.
- Use only fresh brake fluid conforming to Standard FMVSS 116 DOT 4.
- Genuine VW/Audi brake fluid conforms to this specification.
- Brake fluid must not be allowed to come into contact with the paintwork because of its caustic effect.
- Brake fluid is hygroscopic, in other words it absorbs moisture from the surrounding air, and should therefore always be kept in airtight containers.
-- Connect :VAS5234 ; only open the bleeder screws in the specified sequence and bleed brake calipers.
Collect the used brake fluid with the bleeder bottle which is part of the bleeder appliance.
Bleeding sequence:
- Right rear brake caliper
- Left rear brake caliper
- Right front brake caliper
- Left front brake caliper
Press the brake pressure regulator lever firmly toward the rear axle (arrow) when bleeding the rear brakes.
Vehicles equipped with ABS and Electronic Differential Lock (EDL) require a different bleeding sequence Bleeding brake hydraulic system-vehicles with Electronic Differential Lock (EDL) .
Bleeding brakes without :VAS5234 or equivalent brake bleeding appliance
This method should only be used if no brake filling and bleeding device is available.
-- Build up pressure in brake system by pumping pedal.
-- Open bleeder screw with bleeder bottle hose installed.
-- Close bleeder screw with pedal pushed down.
-- Repeat process until no more air escapes
Changing Brake Fluid
Connect brake system to :VAS5234 and, according to specifications in following table, let brake fluid flow out. Used brake fluid will be forced out of system by pumping in new fluid.
| Sequence: Brake Caliper | Quantity of brake fluid to flow out |
|---|---|
| Right rear | 500 cm3 (approx. 1 pt.) |
| Left rear | 500 cm |
| Right front | 500 cm |
| Left front | 500 cm |
Changing Brake Fluid without :VAS5234 or equivalent brake bleeding device
This method should only be used if no brake filling and bleeder appliance is available.
-- Use an extractor bottle to extract as much brake fluid as possible from brake fluid reservoir.
-- With bleeder screw open, pump brake pedal in order to pump brake fluid out of brake master cylinder and brake calipers.
-- Pour in fresh brake fluid and bleed brake system in specified order Bleeding brake hydraulic system .