2000 AUDI A4 Brakes Erase DTC Memory End Output Workshop Manual

01-19

Corrective actions


If a malfunction or problem has been
detected or reported, perform guided
troubleshooting:

- First switch on the ignition, and note whether the
indicator lamps light up. The table in the section
"Overview of indicator lamp functions" for the
relevant system facilitates an initial diagnosis.

- Fulfill test requirements.

- Connect the VAG1551 Scan Tool (ST) and
select the address word 03 "Brake Electronics".

- Check the control module version Parts
Catalog and press the button.

- Check DTC memory. If a DTC is stored: Note
the DTC and erase DTC memory page 01
-
15
.

- End data transfer using the "End Output"
function page 01
-16
.

- Repair the malfunction with the help of the DTC
table. Select again the address word 03 "Brake
Electronics". Check and erase DTC memory.
Pa
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), End Out
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(function 06
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01-20

- End data transfer using the "End Output"
function. Disconnect VAG1551 Scan Tool (ST).

- Make sure all harness connectors are connected
and engaged. Perform a road test. The indicator
lamps must not light up during the drive. If the
indicator lamps light up during the road test,
repeat the troubleshooting procedure.

Note:
If the control module connector is disconnected
during the drive, an unfounded DTC may be
stored in the memory of another control module.
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. Driving the vehicle presents the
risk of accident.

- Always switch off ignition before carrying out
installation or repair work.
Pa
ge 10 of 15 Erase DTC Memor
y (function 05
), End Out
put
(function 06
)
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play?action=Goto&t
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01-21

Only replace a malfunctioning component if you
are certain that all electrical wires to this
component are functioning properly. The lines
must work properly and be capable of carrying
all signals without any problems. Check the
lines for the following:

- Corrosion or loose connections in the
connectors or Ground straps. If there are bent,
broken, or corroded contacts on the
connectors, replace the contacts using
VAS1978 wiring harness repair kit.

- Open circuit in wiring

- Short circuits to B+ or Ground (GND)

Electrical Wiring Diagrams, Troubleshooting &
Component Locations

Welding work performed with electrical welding
equipment can affect the ABS/ESP system.
Pa
ge 11 of 15 Erase DTC Memor
y (function 05
), End Out
put
(function 06
)
11/20/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
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pair&id=AUDI.B5.SU02.01.2

01-22

Test requirements

Vehicle equipped with approved wheel and
tire sizes, which must be the same on all four
wheels. All tire inflation pressures checked
according to specification.
The mechanical/hydraulic components of the
brake system are OK. Hydraulic connections
and lines are sealed properly (visual check
at hydraulic unit, brake calipers, wheel
cylinders, tandem master brake cylinder).
Wheel bearings and wheel bearing play OK
Wheel speed sensors installed correctly

Repair manual, Brake System, Repair Group
45


Supply voltage OK (at least 10.0 volts).
Harness connector is properly connected at
ABS control module -J104-, locking
mechanism is engaged.

Pa
ge 12 of 15 Erase DTC Memor
y (function 05
), End Out
put
(function 06
)
11/20/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
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pair&id=AUDI.B5.SU02.01.2

The OBD sequence can only be started with
the vehicle stationary and the ignition
switched on (or with the engine running). It is
not possible to initiate On Board Diagnostic
(OBD) once wheel speed has reached 2.75
km/h.
Pa
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), End Out
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(function 06
)
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01-23

While testing the ESP system, make sure
that the vehicle's electrical system is not
subjected to electromagnetic interference;
keep the vehicle away from equipment with a
high current draw such as electric welding
units.

WARNING!

The diagnostic will not terminate at a speed
of v = > 20 km/h. Risk of accident!
Pa
ge 14 of 15 Erase DTC Memor
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), End Out
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(function 06
)
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01-24

Technical information required


Valid wiring diagram

Electrical Wiring Diagrams, Troubleshooting &
Component Locations

Installation locations of electrical
components.

Repair manual, Brake System, Repair Group
45


Brake mechanical information

Repair manual, Brake System, Repair Group
46


Brake hydraulic information

Repair manual, Brake System, Repair Group
47

Pa
ge 15 of 15 Erase DTC Memor
y (function 05
), End Out
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(function 06
)
11/20/2002 htt
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play?action=Goto&t
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pair&id=AUDI.B5.SU02.01.2