Bleeding of the brake system is carried out using the VAG 1869 bleeding unit. Connect the bleeding unit in accordance with the operating instructions.
Remove the dust cap from the caliper bleeder nipple, clean it and put one end of a clean transparent hose on it, lower the other end into a container partially filled with brake fluid. The container should be at least 300 mm above the bleeder nipple. This prevents air from entering the caliper through the thread of the bleeder nipple.
Unscrew the bleed nipple of the corresponding brake caliper by half a turn and wait until brake fluid without air bubbles comes out of the nipple, then screw the bleed nipple back on.
Bleed the brakes in the following sequence:
- 1 - rear right brake caliper;
- 2 - rear left brake caliper;
- 3 - Front right brake caliper;
- 4 - front left brake caliper.
On vehicles with electronic stability control (ESP) bleed the brakes in the following sequence:
- 1 - rear left brake caliper;
- 2 - Front right brake caliper;
- 3 - rear right brake caliper;
- 4 - front left brake caliper.
Replacing brake fluid (every 2 years)
Brake fluid is hygroscopic (absorbs moisture from the air), therefore, it is not recommended to use liquid stored for a long time in an open container.
Brake fluid should not come into contact with mineral oils. Even a small amount of mineral oil makes the brake fluid unsuitable for use in the brake system.
Use only fresh DOT 4 brake fluid.
Replace the brake fluid using the VAG 1869 bleeding unit. Connect the bleeding unit in accordance with the operating instructions.
Open the expansion tank of the hydraulic brake system and fill it with brake fluid to prevent air from entering the brake system from the tank.
Remove the dust cap from the rear right caliper bleeder nipple, clean it and attach one end of a clean transparent hose to it, lower the other end into a container partially filled with brake fluid.
Start the engine and unscrew the bleeder screw on the brake caliper a few turns. Press the brake pedal, forcing the brake fluid out of the expansion tank until the fluid level drops to the point where the fluid supply hose connects to the clutch.
Collect the leaking liquid in a container. Screw on the bleed nipple.
Connect the bleeding unit in accordance with the operating instructions for the bleeding unit VAG 1869.
On vehicles with a manual transmission, install a clean transparent hose on the clutch slave cylinder bleeder nipple, unscrew the nipple a few turns and drain about 100 cm³ of brake fluid. Screw the bleeder nipple back on.
Perform the following actions sequentially on the following calipers:
- 1 - rear right;
- 2 - rear left;
- 3 - front right;
- 4 - front left.
Remove the dust cap from the caliper bleeder nipple, clean it and put a clean transparent hose on it, lower the other end into a container partially filled with brake fluid.
Loosen the bleed screw a few turns and drain approximately 250 cm³ of brake fluid.
The incoming fresh brake fluid flushes away the remains of the old brake fluid in the hydraulic circuit of the brake system.
Screw on the bleed screw.
Disconnect the hose from the brake system expansion tank.
Check the force applied to the pedal. The free travel of the brake pedal should be 1/3 of the pedal travel.