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Stan, Mercedes Technician
Category: Mercedes
Satisfied Customers: 3526
Experience:  Technical support engineer
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hi, i have a mercedes 230 slk auto kompressor. after driving

Customer Question

hi, i have a 1999 mercedes 230 slk auto kompressor. after driving for about 20 mins when you press the brake pedal it sticks on and the pedal starts to depress itself and bind on. you have to tap the pedal to release the brakes. i have had the brake master cylinder changed , that didn't cure it. changed the ABS pump and that didn't solve it. my mechanic is now scratching his head. can you help?

Submitted: 3 years ago.
Category: Mercedes
Expert:  Shantal-Mod replied 3 years ago.

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Expert:  Stan replied 3 years ago.
Please try t drive with ABS pump electrics disconnected. If problem disappears- issue is caused by the BAS (Brake Assyst) subfunction of the ESP/ABS. You might have a separate control unit for it on the Brake booster, or it can be part of ESP control unit. This depends on the VIN of your car.
If problem does not disappear (very unlikely)- cause is in brake mechanics.

Such symptom is most likely caused by the faulty BAS control unit.
It requires Star Diagnosis computer to check the electronics properly