wheel AUDI A4 1998 B5 / 1.G Brakes ESP Electrical Testing Workshop Manual

01-303

Note:
The operation manual for the VAS1978 wiring
harness repair kit generally forbids the repair of
any lines in the ABS or related systems. This rule
only pertains to the shielded lines in these
systems.

Ignition and electrical consumers switched
off before beginning testing (headlights,
lighting, fan, etc.).
For steps 13 through 16, raise the vehicle
until the wheels rotate freely. On vehicles
with manual transmission put the gear shift
lever in neutral. On vehicles with automatic
transmission move the selector lever to
position "N".
Pa
ge 3 of 65 Electronic Stabilization Pro
gram
(ESP
), electrical testin
g
11/20/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.SU02.01.16

01-306
Terminal allocation, ABS control module -J104- Multi-pin connector at ABS control module
(w/EDL) -J104- Terminal
Connected to...

Terminal
1

Voltage supply, terminal 15
Traction control switch
-
5
2
ABS return flow pump relay -J105- (B+)
ABS solenoid valve relay -J106- (B+)
Voltage supply for steering angle sensor -G85- via
terminal 15
86
86
5
3
Hydraulic unit; activation of left front ABS outlet
valve -N102-
15
4
Hydraulic unit; activation of right rear ABS outlet
valve -N135-
12
5
Hydraulic unit; activation of left front ABS inlet
valve -N101-
8
6
Hydraulic unit; activation of right rear ABS inlet
valve -N133-
2
7
ABS return flow pump relay -J105- (GND)
85
8
Left front ABS wheel speed sensor -G47-
For vehicles with all-wheel-drive:
-
Pa
ge 6 of 65 Electronic Stabilization Pro
gram
(ESP
), electrical testin
g
11/20/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.SU02.01.16

01-307

Multi-pin connector at ABS control module (w/EDL) -
J104- Terminal
Connected to...

Terminal
9
Left front ABS wheel speed sensor -G47-
For vehicles with front-wheel-drive:
-
10
Left front ABS wheel speed sensor -G47-
(GND)
-
11
Right rear ABS wheel speed sensor -G44-
-
12
Right rear ABS wheel speed sensor -G44-
(GND)
-
13
Left rear ABS wheel speed sensor -G46-

14
Left rear ABS wheel speed sensor -G46- (GND)
-
15
Right front ABS wheel speed sensor -G45-
-
16
Right front ABS wheel speed sensor -G45-
(GND)
-
17
Not assigned
-
Electrical Wiring Diagrams, Troubleshooting & Component Locations
Pa
ge 8 of 65 Electronic Stabilization Pro
gram
(ESP
), electrical testin
g
11/20/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.SU02.01.16

01-309

Multi-pin connector at ABS control module
(w/EDL) -J104- Terminal
Connected to...

Terminal
25
Hydraulic unit; activation of left rear ABS outlet valve -
N136-
11
26
Hydraulic unit; activation of right front ABS inlet valve -N99-

5
27
Not assigned
-
28
Ground (GND) supply, terminal 31
-
29
Ground (GND) supply, terminal 31
-
30
Not assigned
-
31
Instrument cluster; activation of traction control indicator
light; (control module 4B0 907 389)
15
31
Rear left wheel speed sensor output; (control module 8D0
907 389/A/D/E)
-
32
Instrument cluster; ABS/EDL warning light activation
26
33
Not assigned
-
Electrical Wiring Diagrams, Troubleshooting & Component Locations
Pa
ge 10 of 65 Electronic Stabilization Pro
gram
(ESP
), electrical testin
g
11/20/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.SU02.01.16

01-314

Multi-pin connector at ABS control
module (w/EDL) -J104- Terminal
Connected to...

Terminal
70
Left-rear wheel speed sensor output; (control module 4B0
907 389)
EWD
70
Instrument cluster; activation of traction control indicator
light (control module 8D0 907 389/A/D/E)
15
71
Speed sensor output rear right
EWD
72
not occupied; (control module 4B0 907 389)
-
72
Front left wheel speed sensor output; (control module 8D0
907 389/A/D/E)
EWD
73
not occupied; (control module 4B0 907 389)
-
73
Front right wheel speed sensor output; (control module 8D0
907 389/A/D/E)
EWD
74
Not assigned
-
75
Sensor for transverse acceleration -G200-; voltage supply;
(control module 4B0 907 389)
3
75
not occupied; (control module 8D0 907 389/A/D/E)
-
76
Parking brake warning light switch -F9-
EWD
Electrical Wiring Diagrams, Troubleshooting & Component Locations
Pa
ge 15 of 65 Electronic Stabilization Pro
gram
(ESP
), electrical testin
g
11/20/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.SU02.01.16

01-320

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
6 52 + 54

High pressure switch
valve -1- traction control
-N227-


W
16
- Check electrical wiring for short
circuit to Ground (GND) or B+.


High pressure switch
valve -2- traction control
-N228- Electrical Wiring Diagrams,
Troubleshooting & Component
Locations
- If the electrical wiring is OK,
replace the hydraulic unit.
7
8 + 10
1)
9 + 10 2) Left front ABS wheel speed
sensor -G47-
400
2300
- An infinitely high resistance
indicates an open circuit. Check for
this.
Outlets on ABS control module -J104- differ depending on installed equipment
1) Vehicles with all-wheel-drive
Pa
ge 21 of 65 Electronic Stabilization Pro
gram
(ESP
), electrical testin
g
11/20/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.SU02.01.16

2) Vehicles with front-wheel-drive
Pa
ge 22 of 65 Electronic Stabilization Pro
gram
(ESP
), electrical testin
g
11/20/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.SU02.01.16

01-321

Resistance measurement: Select measurement range on VAG1526 (2k or 20 k )





Test
step VAG
1598/20
sockets Test of
Test
requirements
- Additional work
steps Specified
value Corrective action
8 15 + 16 Right front ABS
wheel speed
sensor -G45-
- A resistance less than the specified value
indicates a short circuit between both lines.
Check for this.
9 13 + 14 Left rear ABS
wheel speed
sensor -G46-
400
2300
- Check electrical wiring for short circuit to
Ground (GND) or B+.
10 11 + 12 Right rear ABS
wheel speed
sensor -G44- Electrical Wiring Diagrams,
Troubleshooting & Component Locations - If the electrical wiring is OK, replace the
relevant ABS wheel speed sensor.
Pa
ge 23 of 65 Electronic Stabilization Pro
gram
(ESP
), electrical testin
g
11/20/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.SU02.01.16

01-323
Electrical test; steps 13-27

Function test
Test
step VAG
1598/20
sockets Test of
Test requirements
- Additional work stepsSpecified
value Corrective action
13
1)
Bridge
1 + 2,
28+37
2)
28+36 3) Inlet valve -N101
and front left
brake line
connection
Ignition on

- for vehicles with
automatic transmission,
engage neutral position
"N"
- Bridge terminals 5 +
28
- Depress brake pedal
and hold.
Left front
wheel can
be rotated
by hand - If the wheel does not rotate, check the
other wheels for free rotation. If yes, then
hydraulic brake lines are mixed-up
(switched). Check brake line connections
and coupling pieces. Make sure every
component is OK.

See continuation on next page
Outlets on ABS control module -J104- differ depending on installed equipment
1) This test step requires two technicians.
Pa
ge 25 of 65 Electronic Stabilization Pro
gram
(ESP
), electrical testin
g
11/20/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.SU02.01.16

01-324
Continuation: Function test
Test
step VAG
1598/20
sockets Test of
Test
requirements
- Additional work
steps Specified value
Corrective action
13
1)
Bridge
1 + 2,
28+37
2)
28+36 3) Inlet valve -N101 and
front left brake line
connection
- If all wheels are blocked, inlet
valve is malfunctioning DTC
table, DTC 00257.

- Remove bridge
The left-front
wheel remains
locked.

- Release brake
pedal.
Outlets on ABS control module -J104- differ depending on installed equipment
1) This test step requires two technicians. 2) Vehicles with control module 4B0 907 389
Pa
ge 27 of 65 Electronic Stabilization Pro
gram
(ESP
), electrical testin
g
11/20/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.SU02.01.16