Antilock Brakes / Traction Control Systems: Locations
ABS/Electronic Stabilization Program Component Overview and Component Locations, Bosch 8.0
• The luggage compartment liner in the front of the luggage compartment must be removed for all work on the brake booster, brake master cylinder, ABS Hydraulic Unit (N55), ABS Control Module (J104) and Brake System Vacuum Pump (V192).
The following versions are possible with Bosch 8.0 ABS:
• ABS/EDL/ASR/ESP
The brake system is distributed diagonally. The vacuum brake servo unit boosts the brakes pneumatically.
• 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.
1 - ABS/ESP Control Lamp (K155)
• Component location: In the 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 the ASR is switched off.
• Comes on during sensor programming if:
• The battery was disconnected and connected.
• Vehicle was started with jump start.
• The battery is too weak.
• After the sensor programming procedure, the ESP light goes out after driving a short distance.
2 - Brake Pad Wear Indicator Lamp (K32)
• Located in the Driver Information System, center display field.
• Comes on when the brake pad wear limit is reached.
3 - Brake System Warning Lamp (K118)
• Located in the tachometer.
• Lights up when the parking brake is engaged.
• Comes on when there is an ABS system malfunction.
• Blinks when brake fluid is too low.
4 - ABS Warning Lamp (K47)
• Component location: In the 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.
5 - Steering Angle Sensor (G85)
• Removing and Installing, refer to => [ Steering Angle Sensor ] Service and Repair.
• Component location: Installed in coil ring with slip ring on steering column.
• Perform zero adjustment using the Vehicle diagnosis, testing and information system (VAS 5051B) or (VAS 5052).
6 - ASR/ESP Button (E256)
• Component location: in center console.
• Switches the ASR off and on.
7 - Parking Brake Lever with Contact Switch
• Removing and Installing, refer to => [ Parking Brake Lever ] Parking Brake Lever.
• Located in the center console.
8 - Brake Pedal
• With a mount for the brake pedal switch.
• Removing and Installing, refer to => [ Brake Pedal ] Brake Pedal.
9 - Brake Pedal Switch (F47)
• Removing and Installing, refer to => [ Brake Pedal Switch ] Service and Repair.
• Component location: On brake pedal.
• Can be tested in guided fault finding with the vehicle diagnosis, testing and information system (VAS 5051B) or (VAS 5052).
• A brake lamp sensor may be installed depending on the version.
• Brake lamp sensor, removing and installing, refer to => [ Brake Lamp Sensor ] Service and Repair.
10 - ESP Sensor Unit (G419)
• 9 Nm
• Removing and installing, refer to => [ Electronic Stabilization Program Sensor Unit ] Electronic Stabilization Program Sensor Unit.
• Component location: under the cover behind the seats.
• Combined transverse acceleration sensor, rotation rate sensor and longitudinal acceleration sensor.
• Can be tested in guided fault finding with the vehicle diagnosis, testing and information system (VAS 5051B) or (VAS 5052).
• Observe installation instructions.
11 - Brake Master Cylinder
• Removing and installing, refer to => [ Brake Master Cylinder ] Brake Master Cylinder.
12 - Brake Booster
• Removing and Installing, refer to => [ Brake Booster ] Brake Booster.
13 - Brake Fluid Reservoir
• Removing and installing, refer to => [ Brake Fluid Reservoir ] Service and Repair.
• With the brake fluid level warning switch (F34).
14 - Vacuum Pump (V192)
• Removing and installing, refer to => [ Brake System Vacuum Pump ] Brake System Vacuum Pump.
15 - Right Front ABS Wheel Speed Sensor (G45)/Left Front ABS Wheel Speed Sensor (G47)
• Removing and installing, refer to => [ Front ABS Wheel Speed Sensor ] Front ABS Wheel Speed Sensor.
• Can be tested in "guided fault finding" with the vehicle diagnosis, testing and information system (VAS 5051B) or (VAS 5052).
16 - Right Rear ABS Wheel Speed Sensor (G44)/Left Rear ABS Wheel Speed Sensor (G46)
• Removing and Installing, refer to => [ Rear ABS Wheel Speed Sensor ] Rear ABS Wheel Speed Sensor.
• Can be tested in "guided fault finding" with the vehicle diagnosis, testing and information system (VAS 5051B) or (VAS 5052).
17 - Diagnostic Connection
• Component location: Cover in driver footwell.