Page 23 of 79

01-77
Resistance measurement: Select measurement range on VAG1526 (200 )
Test step
VAG
1598/20
sockets Test of
Test requirements
- Additional work steps Specified
value Corrective action
5
Note:
Only for
vehicles with
ABS/EDL or
ASR 3 + 55 Left front traction
control switch-over
valve -N168-
(secondary piston
circuit)
Right front traction
control switch-over
valve -N166- (primary
piston circuit) Electrical wiring
between control
module and hydraulic
unit OK 12
28
Electrical Wiring Diagrams,
Troubleshooting & Component
Locations - Check electrical wiring
between control module and
hydraulic unit for short circuit
to Ground (GND) or B+. - If the electrical wiring is OK,
replace the hydraulic unit.
6
Note:
Only for
vehicles with
ABS/EDL or
ASR 4 + 27 Left front traction
control outlet valve -
N169- (secondary
piston circuit)
Right front traction
control outlet valve -
N167- (primary piston
circuit)
Electrical wiring
between control
module and hydraulic
unit OK 12
28
Electrical Wiring Diagrams,
Troubleshooting & Component
Locations - Check electrical wiring
between control module and
hydraulic unit for short circuit
to Ground (GND) or B+. - If the electrical wiring is OK,
replace the hydraulic unit.
Pa
ge 23 of 79 Read Measurin
g Value Block
(function 08
)
11/20/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.SU02.01.8
Page 24 of 79

01-78
Resistance measurement: Select measurement range on VAG1526 (2k or 20 k ) Test
step VAG
1598/20
sockets Test of
Test requirements
- Additional work stepsSpecified
value Corrective action
7
9 + 10
1)
2)
35 + 10
3)
5)
36 + 10
4) Left front ABS
wheel speed
sensor -G47-
- Check electrical wiring between
control module and wheel speed
sensor for short circuit to Ground
(GND) or B+
8
15 + 14 1)
3) 4)
42 + 14 2)
5) Right front
ABS wheel
speed sensor
-G45-
Electrical wiring between
control module and
wheel speed sensor OK 400 2300
Electrical Wiring Diagrams,
Troubleshooting & Component
Locations
9 13 + 12 Left rear ABS
wheel speed
sensor -G46-
- If the electrical wiring is OK,
replace the relevant ABS wheel
speed sensor.
10 11 + 38 Right rear
ABS wheel
speed sensor
-G44- Outlets on ABS control module -J104- differ depending on installed equipment
Pa
ge 24 of 79 Read Measurin
g Value Block
(function 08
)
11/20/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.SU02.01.8
Page 26 of 79

01-79
Resistance measurement: Select measurement range on VAG1526 (200 ) Test
step VAG
1598/20
sockets Test of
Test requirements
- Additional work stepsSpecified
value Corrective action
11 2 + 37 ABS solenoid
valve relay -
J106- Electrical wiring between
control module and
hydraulic unit OK 30
80
Electrical Wiring Diagrams,
Troubleshooting & Component
Locations - Check electrical wiring between
control module and hydraulic unit for
short circuit to Ground (GND) or B+. - If electrical wiring is OK, replace the
relay.
12 2 + 7 ABS return
flow pump
relay -J105-
Electrical wiring between
control module and
hydraulic unit OK 30
80
Electrical Wiring Diagrams,
Troubleshooting & Component
Locations - Check electrical wiring between
control module and hydraulic unit for
short circuit to Ground (GND) or B+. - If electrical wiring is OK, replace the
relay.
Pa
ge 26 of 79 Read Measurin
g Value Block
(function 08
)
11/20/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.SU02.01.8
Page 44 of 79

01-89
Function test: ABS warning light -K47-
Test step
VAG
1598/20
sockets Test of
Test
requirements
- Additional work
steps Specified value
Corrective action
19
Continuation: - Function of
ABS
warning
light -K47- - Switch on
ignition ABS warning
light -K47- lights
up for two (2)
seconds and
then goes out.
Electrical Wiring Diagrams,
Troubleshooting & Component Locations - If ABS warning light does not come on,
check voltage of electrical system and test
wiring from terminal 32 of ABS control
module -J104- to instrument cluster for
short circuit to Ground (GND).
- The ABS warning lamp does not switch
off after 2 seconds. The red "brake system
malfunction" symbol lights up after 2
seconds. Check wire from terminal 32 of
ABS control module -J104- to instrument
cluster for short circuit to B+ and open
circuit.
Repair Manual, Electrical Equipment,
Repair Group 90; Instrument cluster
- Are both the vehicle voltage and the
wiring from terminal 32 of ABS control
module -J104- to the instrument cluster
OK? Malfunction in instrument cluster. Pa
ge 44 of 79 Read Measurin
g Value Block
(function 08
)
11/20/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.SU02.01.8
Page 48 of 79

01-93
Function test: Traction control indicator light -K86-. This is only installed if vehicle is equipped with ASR.
Test step
VAG
1598/20
sockets Test of
Test
requirements
- Additional work
steps Specified value
Corrective action
21
Continuation: - Function of
traction
control
indicator light
-K86- - Switch on
ignition Traction control
indicator light -K86-
comes on for two
(2) seconds and
then goes out.
Electrical Wiring Diagrams,
Troubleshooting & Component
Locations - If traction control indicator light does
not light up, check vehicle voltage and
wire from terminal 31 of ABS control
module -J104- to instrument cluster for
short circuit to B+ and open circuit.
- If traction control indicator lamp
remains continuously lit, check wire
from terminal 31 of ABS control
module -J104- to instrument cluster for
short circuit to Ground (GND).
Repair Manual, Electrical
Equipment, Repair Group 90; Instrument cluster
- Are both the vehicle voltage and the
wiring from terminal 31 of ABS control
module -J104- to the instrument
cluster OK? Malfunction in
instrument cluster.
Pa
ge 48 of 79 Read Measurin
g Value Block
(function 08
)
11/20/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.SU02.01.8
Page 50 of 79
01-95
Function test: Traction control button; set measurement range on VAG1526: 20 V =
Test step
VAG
1598/20
sockets Test of
Test requirements
- Additional work
steps Specified
value Corrective action
22 28 + 44 Function of
traction control
button Ignition switched
on.
Continuation:
- Traction control
button not pressed 0.0 to 0.5
V
- Traction control
button pressed 10.0 to 14.5
V
Electrical Wiring Diagrams,
Troubleshooting & Component
Locations - Check wire from terminal 28 to
Ground (GND).
- Check wire from terminal 44 to
traction control button, terminal 6.
- Check voltage supply from terminal 5
of traction control button to terminal 15.
- If no malfunctions can be found using
the procedures in these steps, replace
the traction control button.
Pa
ge 50 of 79 Read Measurin
g Value Block
(function 08
)
11/20/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.SU02.01.8
Page 51 of 79
01-96
Voltage measurement; set measurement range on VAG1526: 20 V =
Test
step VAG
1598/20
sockets Test of
Test
requirements
- Additional work
steps Specified
value Corrective action
23 1 + 28
1 + 29 Voltage supply to ABS
control module -J104- via
terminal 15 Ignition
switched on. 10.5 to 14.5
V
Electrical Wiring Diagrams,
Troubleshooting & Component
Locations - Check wiring from terminals 28
and 29 to Ground (GND).
- Check wire from terminal 1 to
terminal 15.
Pa
ge 51 of 79 Read Measurin
g Value Block
(function 08
)
11/20/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.SU02.01.8
Page 54 of 79

01-99
Output on printer of
VAG1551 Scan Tool
(ST) Possible cause
Corrective action
DTC
00257
Left front ABS inlet
valve -N101-
Open circuit, short circuit to B+ or Ground (GND)
in wiring between ABS hydraulic unit -N55- and
ABS control module -J104-.
Left front ABS inlet valve -N101- malfunctioning - Carry out "electrical test", steps 1 + 13
page 01
-68
.
- If the electrical test does not reveal any
malfunctions, check all wiring and
connectors for loose contacts.
- If no problems are found after
implementing the specified steps, replace
the control module.
00259
Right front ABS inlet
valve -N99-
Open circuit, short circuit to B+ or Ground (GND)
in wiring between ABS hydraulic unit and ABS
control module -J104-.
Right front ABS inlet valve -N99- malfunctioning. - Carry out "electrical test", steps 2 +14
page 01
-68
.
- If the electrical test does not reveal any
malfunctions, check all wiring and
connectors for loose contacts.
- If no problems are found after
implementing the specified steps, replace
the control module.
Pa
ge 54 of 79 Read Measurin
g Value Block
(function 08
)
11/20/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.SU02.01.8