Hydraulic System: Adjustments

Brake Pressure Regulator, Checking and Adjusting

Special tools, testers and auxiliary items required

• Brake pressure gauge 0-250 bar (V.A.G 1310 A)

The brake pressure regulator is fastened to a retainer placed on the mounting bracket for the rear axle and is controlled via a spring from the rear axle.





Function Check

Press down brake pedal firmly and release quickly (vehicles stands on its wheels). For this, brake booster lever must move.

Pressure Test and Adjusting

Brake booster is adjusted at curb weight of vehicle.

Curb weight is defined as follows: Vehicle weight ready for operation, this includes:

• Driver of 75 kg.

• Fuel tank must be completely filled.

• Spare tire, vehicle tools and vehicle jack are installed in appropriate position in vehicle.

• The water container for the windshield/headlight cleaning system must be completely filled.

- Raise vehicle and connect pressure gauge at brake caliper (left front wheel) and at wheel brake cylinder/brake caliper (right rear wheel).

- Bleed both gauges.

- Lower vehicle and jounce and rebound at rear axle several times.

- Depress brake pedal and measure pressures.

- Compare measured pressure values with adjustment values , adjust if necessary.

Load-Dependent Brake Pressure Regulator, Adjustment Values





Brake Pressure Regulator, Adjusting

Test pressure at rear axle too high:

- Release regulator spring.

Test pressure at rear axle too low:

- Tighten regulator spring.

Do not adjust when brake pedal is depressed, observe the following repair sequence:

Read values:

- Release pedal.

- Adjust spring.

Depress pedal again:

- Read values and adjust if necessary.

- Remove pressure gauge, bleed brake system => [ Brake System Bleeding General Information ] Brake System Bleeding General Information.