Deactivating & Activating SENSOTRONIC Brake Control (SBC) System (Without Star Diagnosis Compact Diagnosis System)

Brake pad replacement and brake bleeding must not be carried out simultaneously. Before working on SBC system, SBC self-test must be prevented or brake pistons will move out automatically. Brake pedal MUST NOT be pressed under any circumstances or brake pistons will move out automatically. Inadvertent operation of brake pedal MUST BE prevented. Before starting work, it is absolutely essential to read through complete work description, operations have to be completed in rapid succession. To carry out the operations correctly a second person must be present, certain signals cannot be seen by one person. If work procedure is revised or timing specifications are not maintained, work cannot be carried out correctly.

1. Place vehicle onto lift.
2. Open driver's window.
3. Switch off all electrical consumers and remove key from ignition switch. Vehicles with Keyless Go, press Start/Stop button repeatedly until ignition is switched off.
4. Remove Keyless Go cards or key from vehicle and store outside of transmitter range Close and lock all doors, for a minimum of 30 seconds (t1). See Fig 1 . During this time run-on of SBC brake system elapses.
NOTE: Brake pedal MUST NOT be pressed.
5. Unlock vehicle for a minimum of 15 seconds (t2), SBC self-test may run during this time.
WARNING: The vehicle MUST NOT be unlocked under any circumstances during work on brake system. The SBC brake pad application will be started if any door is unlocked and brake pads will be applied.
6. Lock vehicle, after 15 seconds, the following procedures can be performed:
   • Remove/Install front or rear brake pads. See BRAKE PADS (FRONT)  or BRAKE PADS (REAR)  under REMOVAL & INSTALLATION.
   • Remove/Install front or rear brake discs. See BRAKE DISC (FRONT & REAR)  under REMOVAL & INSTALLATION.
   • Remove/Install parking brake shoes. See PARKING BRAKE SHOES  under REMOVAL & INSTALLATION.
   • Remove/Install brake hoses. See BRAKE HOSES  under REMOVAL & INSTALLATION.
   After performing procedures, SBC brake system must be reactivated.
7. To activate SBC brake system, hydraulic unit temperature must be 176°F (80°C) or less.
8. Raise vehicle until wheels are off the ground.
NOTE: Vehicles with Keyless Go, DO NOT activate any Keyless Go functions.
9. Turn ignition ON (Z2). See Fig 2 .
NOTE: DO NOT start engine.
10. Turn ignition OFF (Z0), wait 1-5 seconds (t2), turn ignition ON (Z0) .
11. Rotate left rear wheel in running direction for a minimum of 3 seconds (t4) (1-2 revolutions) and bring wheel to a stop.
12. Rotate left front wheel a minimum of 2 revolutions in running direction within 60 seconds (t5) of rotating left rear wheel. Wheel will be braked automatically, brake lights will flash 3 times to signify successful activation. The SBC brake pad application routine will start and front and rear brake pads will be applied several times. After 50 seconds, SBC brake pad application routine is ended.
13. Lower vehicle and turn OFF ignition (Z0).
14. Start engine and press brake pedal 5-10 times. If a fault message appears in multifunction display, repeat SBC brake pad application routine from step  7 . If fault message continues to be displayed after repeating SBC brake pad application routine 2-3 times, connect STAR DIAGNOSIS compact diagnosis system and apply brake pads according to menus on display. See Figure .
15. Pull and erase diagnostic trouble codes according to menus on display.

Fig 1: Preventing SBC Self-Test & Applying Brake Pads (Without Star Diagnosis Compact Diagnosis System) (1 Of 2)

Courtesy of MERCEDES-BENZ OF NORTH AMERICA.

Fig 2: Preventing SBC Self-Test & Applying Brake Pads (Without Star Diagnosis Compact Diagnosis System) (2 Of 2)

Courtesy of MERCEDES-BENZ OF NORTH AMERICA.