ECU AUDI A4 1999 B5 / 1.G Brakes Basic Setting 04 Workshop Manual

01-251

WARNING!

While system is in diagnostic, the
ABS/ESP/EBD is not active. Driving the
vehicle after On Board Diagnostic (OBD) has
detected a malfunction presents the risk of
accident. The brake system will only be
partially functional. Because brake pressure
at the rear wheels is no longer regulated vie
Electronic Brake Distribution (EBD), the rear
wheels tend to brake excessively. This
causes the rear of the vehicle to break loose.

When the use of test equipment is required
during road tests, test equipment must
always be secured to the rear seat and
operated from there by a second person. If
test and measuring equipment is operated
from the passenger seat, the person seated
there could be injured in the event of an
accident involving deployment of the
passenger-side airbag.
Pa
ge 10 of 64 Basic settin
g (scan tool function 04
)
11/20/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.SU02.01.15

01-258
Test table: display group 1
Notes:

Display fields 1 through 4 show the current wheel circumference speeds in km/h. These are calculated by the ABS control
module -J104- on the basis of the signals received from the wheel speed sensors. If one of the display fields shows no
reading, proceed as for DTCs 00283, 00285, 00287, 00290 "ABS Wheel Speed Sensor" DTC table page 01
-357
.
In order to check whether wheel speed sensors are properly allocated to each wheel, the vehicle must be raised. On
vehicles with manual transmission put the gear shift lever in neutral. On vehicles with automatic transmission move the
selector lever to position "N". Turn appropriate wheel by hand. Remaining drive wheels must be secured against turning.
When a vehicle is accelerated uniformly on a dry surface, the displayed value will increase continuously by whole
numbers; e.g. 6 km/h, 7 km/h, 8 km/h ... . The difference between displayed values 1-4 should not be more than 1 km/h
(error from out-of-round wheels). If the values jump, for instance from ...6km/h, 7 km/h, to 12 km/h...or if the difference
between the displayed values is greater than 1 km/h, then check the installation of the wheel speed sensors and rotors. Repair Manual, Brake System, Repair Group 45

Pa
ge 17 of 64 Basic settin
g (scan tool function 04
)
11/20/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.SU02.01.15

01-274
Test table: display group 6 Read measuring value
block 6
Indicated on display
0 volts to 18
volts
on
or
off
on
or
off 0 ...
131071


Workshop code:

The workshop code indicates the last workshop that executed the "Login Procedure" (function
11) under address word 03, "Brake electronics" page 01
-237
.
If no code is displayed, the "Login Procedure" under address word 03 "Brake Electronics" has
not been carried out yet.

Voltage at motor for ABS return flow pump:

off specified value, there is no voltage at the motor for the ABS return flow pump. on not permitted during "Read measuring value block", there is voltage at the motor for the ABS
return flow pump.
- Carry out "Electrical test", steps 12, 23 and 24.

ABS solenoid valve relay:

on specified value, relay was activated by ABS control module -J104- during ignition on. off not permitted during "Read measuring value block", the relay was not activated during "ignition on".
- Carry out "Electrical test", steps 11 and 22.
Pa
ge 36 of 64 Basic settin
g (scan tool function 04
)
11/20/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.SU02.01.15