Abs/Electronic Stabilization Program, BOSCH 8.1 Component Overview
The Bosch ESP 8.1 has the following functions:
- ABS - Anti-lock braking system
- ASR - Anti-slip regulation
- EBD - Electronic brake pressure distribution
- EDL - Electronic differential lock
- ESP - Electronic stabilization program
- FBS - Fading brake support
- HBA - Hydraulic brake assist
- MSR - Engine drag torque regulation
- Emergency braking signal
- Brake disc cleaning
- Trailer stabilization
The brake system is distributed diagonally. The vacuum brake servo unit boosts the brakes pneumatically.
NOTE:
ABS disturbances do not affect the brake system and the booster. Conventional brake system stays operative even without ABS. A change in braking behavior should be checked. When the ABS warning lamp comes on the rear wheels can lock-up early when braking!
Malfunction sources are reduced by direct connection of components named. The components are replaced instead of repaired.
- Right Rear ABS Wheel Speed Sensor -G44-
- Removing and Installing REAR ABS WHEEL SPEED SENSORS
- Can be tested in "Guided Fault Finding" with the vehicle diagnosis, testing and information system VAS 5051B or VAS 5052
- Left Rear ABS Wheel Speed Sensor -G46-
- Removing and Installing REAR ABS WHEEL SPEED SENSORS
- ESP-Sensor Unit -G419-
- Component location: Under left seat
- Removing and Installing ELECTRONIC STABILIZATION PROGRAM SENSOR UNIT
- 9 Nm
- Combined Transverse Acceleration Sensor -G200-, Rotation Rate Sensor -G202- and Longitudinal Acceleration Sensor -G251-.
- Can be tested in "Guided Fault Finding" with vehicle diagnosis, testing and information system VAS 5051B or VAS 5052
- Observe installation instructions
- Check arrow in direction of travel when installing
- Brake lamp sensor
- Component location: On brake pedal
- Removing and Installing BRAKE LAMP SENSOR
- Can be tested in "Guided Fault Finding" with vehicle diagnosis, testing and information system VAS 5051B or VAS 5052
NOTE:Cannot be reused after removal.
- Brake pedal
- With bracket for brake lamp sensor
- Removing and Installing, with Manual Transmission BRAKE PEDAL, WITH MANUAL TRANSMISSION
- Removing and Installing, with Automatic Transmission BRAKE PEDAL, WITH AUTOMATIC TRANSMISSION
- Electro-Mechanical Parking Brake Indicator Lamp -K213-
- Located in tachometer.
- Lights up when parking brake is engaged and ignition is switched on,
- Lights up for 20 seconds when parking brake is engaged and ignition is switched off,
- Blinks after engaging parking brake if brake pressure is not sufficient to prevent vehicle from rolling.
- Brake system warning lamp -K118-
- Located in tachometer.
- Lights up with ABS indicator lamp when ABS system malfunctions
- Blinks when brake fluid is too low
- Blinks when there is a brake system malfunction
NOTE:The malfunction is indicated more precisely when the "SET button" in the instrument cluster is pressed.
- ABS warning lamp -K47-NOTE:
The indicator lamp monitors the ABS and the Electronic Differential Lock (EDL).
- Component location: In tachometer
- Lights up for several seconds when ignition is switched on and goes out after an automatic ABS system self-check if there are no malfunctions in the ABS system.
- There is an ABS malfunction if the indicator light:
- Does not light up when ignition is switched on,
- Does not go out after a few seconds,
- Lights up while driving.
- ABS malfunctions have no effect on the brake system. However, a change in braking behavior should be checked.
NOTE:The Electronic Differential Lock (EDL) and ABS work together. The ABS indicator light lights up when the EDL malfunctions.
- ABS/ESP Control Lamp -K155-
- Component location: In tachometer
- Blinks when driving if ESP/ASR engages regularly.
- Comes on when ignition is switched on and goes out after a short self-check.
- Comes on if there is an ESP system malfunction.
- Comes on if there is an ABS system malfunction because ESP and ABS work together.
- Comes on when ASR is switched off.
- Lights up during sensor programming if:
- Battery was disconnected and connected,
- Vehicle was started with jump start,
- Battery is too weak.
- After sensor programming procedure, the ESP light goes out after driving a short distance.
- Left front ABS wheel speed sensor G47
- Removing and Installing FRONT ABS WHEEL SPEED SENSORS
- Can be tested in "Guided Fault Finding" with vehicle diagnosis, testing and information system VAS 5051B or VAS 5052
- ABS Control Module -J104-
- Removing and Installing ABS HYDRAULIC UNIT WITH ABS CONTROL MODULE
- Return ring
- Removing and Installing STEERING ANGLE SENSOR
- Steering Angle Sensor -G85-
- Component location: Installed in coil ring with slip ring on steering column
- Removing and Installing STEERING ANGLE SENSOR
- Perform zero adjustment
Vehicle diagnosis, testing and information system VAS 5051B or VAS 5052
- Right Front ABS Wheel Speed Sensor -G45-
- Removing and Installing FRONT ABS WHEEL SPEED SENSORS
- ASR/ESP Button -E256-
- Component location: In center console
- Switches ASR off and on
- Audi Hold Assist pressure switch
- Located in center console
- Function AUDI HOLD ASSIST
- Removing and Installing AUDI HOLD ASSIST SWITCH
- Parking Brake Pressure Switch -F234-
- Located in center console
- Removing and Installing ELECTRO-MECHANICAL PARKING BRAKE SWITCH
- Data Link Connector (DLC)
- Component location: Cover in driver footwell