1999 AUDI A4 ABS

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

1) Only for vehicles with Front Wheel Drive (FWD) and ABS/EDL Bosch 5 2) Only for vehicles with Front Wheel Drive (FWD) and ABS/ASR Bosch 5 3) Only for vehicles with All Wheel Drive (AWD) and ABS/EDL Bosch 5, (ABS) pressure regulation 4) Only for vehicles with Front Wheel Drive (FWD) and ABS Bosch 5 5) Only for vehicles with All Wheel Drive (AWD) and ABS/EDL Bosch 5, throttle valve regulation
Pa
ge 25 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

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

01-84

Function test and check for proper seal
Test
step VAG
1598/20
sockets Test of
Test requirements
- Additional work stepsSpecified value
Corrective action
17 Bridge
1 + 2,
7 + 37,
37 + 28
ABS return
flow pump -
V39-
Left front
traction
control
switch-over
valve -N168-
Left front
traction
control outlet
valve -N169- Repair Manual,
Brake System, Repair Group 47
- Connect VAG1310A
pressure gauge to front
left brake caliper and
bleed.
- Bridge terminals 3 +
28
Repair Manual, Brake System,
Repair Group 45
- ABS return flow pump
malfunctioning, replace ABS
hydraulic unit -N55-


Pressure
relief valve in
ABS hydraulic
unit -N55-
Left front ABS
outlet valve -
N102- - Switch on ignition for
max. 10 seconds and
switch off again.
Left front
traction control
switch-over
valve -N168-
switched ABS return
flow pump -
V39- runs Pressure on
pressure - Check left front traction control
switch-over valve -N168- and left
front traction control outlet valve -
N169- via resistance test test steps
5 + 6. Replace ABS hydraulic unit -
N55- if malfunctioning.
Pa
ge 35 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

01-85

Function test and check for proper seal
Test step
VAG
1598/20
sockets Test of
Test requirements
- Additional work
steps Specified value
Corrective action
17

Continuation:

Right rear
ABS
outlet
valve -
N135- - Bridge terminals 4 +
28
- Switch on ignition for
max. 10 seconds and
switch off again.
Front Wheel Drive
(FWD):
170 25 bar
All-Wheel Drive
(AWD), pressure
regulation (ABS):
90 25 bar
Left front
traction control
outlet valve -
N169- switchedPressure
increases on
pressure
gauge:
- Pressure relief valve and/or left
front ABS outlet valve -N102-
and/or right rear ABS outlet valve
-N135- malfunctioning. Replace
ABS hydraulic unit -N55-.

- Remove VAG1310A
pressure gauge and
bleed brakes All Wheel Drive
(AWD), throttle
valve regulation:
170 25 bar

Pa
ge 37 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

01-86

Function test and check for proper seal
Test
step VAG
1598/20
sockets Test of
Test requirements
- Additional work stepsSpecified value
Corrective action
18 Bridge
1 + 2,
7 + 37,
37 + 28
ABS return
flow pump -
V39-
Right front
traction
control
switch-over
valve -N166-
Right front
traction
control outlet
valve -N167- Repair Manual, Brake
System, Repair Group 47
- Connect VAG1310A
pressure gauge to front
RIGHT brake caliper
and bleed.
- Bridge terminals 55 +
28
Repair Manual, Brake System,
Repair Group 45
- ABS return flow pump
malfunctioning, replace ABS
hydraulic unit -N55-


Pressure
relief valve in
ABS hydraulic
unit -N55-
Right front
ABS outlet
valve -N100- - Switch on ignition for
max. 10 seconds and
switch off again.
Right front
traction control
switch-over
valve -N166-
switched ABS return
flow pump -
V39- runs Pressure on
pressure - Check right front traction control
switch-over valve -N166- and right
front traction control outlet valve -
N167- via resistance test test
steps 5 + 6. Replace ABS hydraulic
unit -N55- if malfunctioning.
Pa
ge 39 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

01-87

Function test and check for proper seal
Test step
VAG
1598/20
sockets Test of
Test requirements
- Additional work
steps Specified value
Corrective action
18

Continuation:

Left rear
ABS
outlet
valve -
N136- - Bridge terminals 27
+ 28
- Switch on ignition for
max. 10 seconds and
switch off again.
Front Wheel Drive
(FWD):
170 25 bar
All-Wheel Drive
(AWD), pressure
regulation (ABS):
90 25 bar
Right front
traction control
outlet valve -
N167- switchedPressure
increases on
pressure
gauge:
- Pressure relief valve and/or right
front ABS outlet valve -N100-
and/or left rear ABS outlet valve -
N136- malfunctioning. Replace
ABS hydraulic unit -N55-.

- Remove VAG1310A
pressure gauge and
bleed brakes All Wheel Drive
(AWD), throttle
valve regulation:
170 25 bar

Pa
ge 41 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

01-88

Function test: ABS warning light -K47-
Test
step VAG
1598/20
sockets Test of
Test requirements
- Additional work stepsSpecified
value Corrective
action
19 - Function of ABS
warning light -K47- DTC memory checked and no DTC present
in DTC memory of ABS control module -
J104-. Ignition switched off Multi-pin connector connected to ABS
control module -J104- and retainer catch
engaged.
Test step 19: Continued on
next page.
Pa
ge 43 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