Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Abs General Information
The ABS brake system is divided diagonally (two circuits). The vacuum brake servo unit boosts the brakes pneumatically.
Vehicles with ABS Mark 60 or ABS Mark 70 do not have a mechanical brake pressure regulator. A specially coordinated software program in the control module determines brake pressure allocation at the rear brakes.
ABS disturbances do not affect the brake system and the booster. Conventional brake system stays operative even without ABS. A change in braking behavior should be checked. When the ABS Warning Lamp -K47- is lit up, the rear wheels may lock prematurely during braking!
ABS allocation.
1 - Hydraulic unit and control module
2 - Brake Booster
Control module -1- and hydraulic unit -2- comprise a single unit. Separation can only be performed when removed from vehicle. The hydraulic pump -3- must not be separated from the hydraulic unit.
Separation is not possible on vehicles with ABS/EDL/ASR/ESP with hydraulic brake booster or hill assist.
NO RELATED
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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.