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.