Mercedes series 211, 219 and 230 - Reduced brake power | HELLA
Mercedes Benz
Model series 211, 219 and 230
All models with electro-hydraulic brake system
Sensotronic Brake Control (SBC)
Message on instrument cluster:
"Reduced brake power/increased braking distance! Start engine!"
No error code issued in the control unit
If the above error message is displayed after a longer vehicle downtime period, this may be due to a leak inside the SBC hydraulic unit. The SBC pump my also start up more frequently without the brake being actuated.
In such cases, proceed as follows:
- Connect the diagnostic unit
- Start the engine
- Press the brake pedal repeatedly to increase the pressure in the pressure accumulator
- Read off the actual values/parameters (illustration)
-
- Pressure accumulator approx. 150 bar
- Read off the pressure in the pressure accumulator after 15, 30, 45 and 60 minutes
If the pressure drops by more than 7 bar within 60 minutes, the SBC hydraulic unit needs replacing.
Note
No other actions, e.g. opening/closing the doors or operating the brakes, must be performed during the pressure loss test.
Important safety note
Technical information and practical tips have been compiled by HELLA in order to provide professional support to vehicle workshops in their day-to-day work. The information provided on this website is intended for use by suitably qualified personnel only.
Reprinting, distribution, reproduction, exploitation in any form or disclosure of the contents of this document, even in part, is prohibited without our express, written approval and indication of the source. The schematic illustrations, pictures and descriptions serve only for the purposes of explanation and representation of the instructions and cannot be used as a basis for installation or assembly work. All rights reserved.
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