steering wheel AUDI A4 1999 B5 / 1.G Brakes ESP Bosch 5.3 Workshop Manual

01-218

ESP system sensors and components,
description


Control module for ABS with EDL/ASR/ESP -
J104-
The control module is combined with the
hydraulic unit as one unit. It controls the ESP,
ABS, EDL, ASR, EBD and ETR (Engine Torque
Reduction) functions. When ignition is switched
on, the control module performs a self-test. All
electrical connections are monitored constantly
and the solenoid valves are periodically checked
for function. If the control module fails entirely,
only the normal brake system will be available.

Steering angle sensor -G85-
The steering angle sensor is housed together
with the airbag spiral spring/return spring with
slip ring. It is located on the steering column
between the steering column switch and steering
wheel. It transmits the steering wheel's steering
angle to the ABS control module -J104 for
ABS/ASR/ESP via the CAN-bus. After replacing
the control module or the sensor, a zeroing must
be performed. For malfunctioning sensor, the
ESP function is not available.
Pa
ge 2 of 27 Electronic Stabilization Pro
gram
(ESP
) Bosch 5.3
11/20/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.SU02.01.14

01-221

Examples:

During oversteering, the rear of the vehicle breaks out toward the outside
of the curve. The vehicle rotates more on its vertical axis than required to
maneuver through the curve. Braking the outside front wheel counters the
oversteering effect.

In understeering, it is the front of the vehicle that does not follow the
curve. The front of the vehicle breaks out. The vehicle rotates less on its
vertical axis than is required to maneuver through the curve. By braking
the rear inside wheel, the braking force generated intensifies the rotational
movement of the vehicle.
Component locations (except for new components) are the same as for
the Bosch 5.3 components. The procedures for removal and installation of
the components are found in:
Repair manual, Brake System, Repair Group 45

Pa
ge 5 of 27 Electronic Stabilization Pro
gram
(ESP
) Bosch 5.3
11/20/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.SU02.01.14