Risk of injury caused by body parts being jammed or crushed. Risk of injury to skin and eyes caused by brake fluid spraying out at high pressure when working on the SBC brake system - AS42.46-Z-0001-01B

Prevent SBC self-test. 

MODEL 211, 219 with Sensotronic Brake Control (SBC), prevent SBC self-test 

MODEL 230 

Disable the SBC self-test 

Risk of injury 

The SBC brake system periodically carries out a self-test (the PreDriveCheck, PDC) during which high brake pressure is built up. The automatic extension of the brake pistons during the test may result in serious bodily injury (jammed or crushed body parts).

The brake pressure that is built up automatically may cause brake fluid to escape at high pressure, possibly resulting in serious injuries.

Safety precautions/instructions 

Disable the SBC self-test prior to performing any work in the wheel brake area.

Never perform any maintenance or repair work in the wheel brake area without first executing the SBC self-test disable routine.

After the SBC self-test has been disabled, work may only be performed in the wheel brake area (e.g. replacing brake pads and changing brake fluid).

Prior to work on the hydraulic unit or operating unit, the SBC brake system must always  be deactivated using STAR DIAGNOSIS.

Even if the SBC self-test is disabled, the brake pedal must not be pressed, as otherwise high pressure will build up and the brake cylinders will automatically be released.

An SBC self-test sequence may be carried out whenever:

• the vehicle is opened by remote control.
• the driver, front passenger or rear door is opened.
• the trunk is opened.
• the key is turned to position 1 in the ignition lock (EZS).
• the brake pedal is operated.
• the parking brake is released.