1997 AUDI A4 diagram

0 Brake pedal not operated1 Brake pedal operated

Electrical Wiring Diagrams, Troubleshooting & Component
Locations - Check brake light switch if there are deviations.
Brake light switch: Signal for Front
and All Wheel Drive:

0 Brake pedal not operated 1 Brake pedal operated


Electrical Wiring Diagrams, Troubleshooting & Component Locations - Check brake light switch if there are deviations.
Pa
ge 7 of 79 Read Measurin
g Value Block
(function 08
)
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01-71

Connecting the VAG1598/20 test box and
checking the ABS, ABS/EDL or ASR system

- Switch ignition off.

- Remove ABS control module -J104-.

Repair manual, Brake System, Repair Group
45


- Disconnect multi-pin connector from ABS control
module -J104-.

- Check multi-pin connector between harness
connector and ABS control module -J104-.

The socket designations on the VAG1598/20 test box are identical to the
terminal designations on the ABS control module -J104- and on the wiring
harness connector.
Electrical Wiring Diagrams, Troubleshooting & Component Locations - Connect VAG1598/20 test box to multi-pin connector of ABS wiring
harness.
Pa
ge 14 of 79 Read Measurin
g Value Block
(function 08
)
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01-75
Notes:
For test table:

The socket designations of the VAG1598 test box are identical to the terminal designations of the ABS control module
(w/EDL) -J104- in the wiring diagram. Incorrect test procedures can cause damage to the system. Do not bridge any
terminals other than those listed in the table.
Electrical Wiring Diagrams, Troubleshooting & Component Locations Specified values refer to readings on the VAG1526 and are not necessarily applicable for other test units.
If the measured values do not match specifications, carry out the corrective actions listed on the right side of the table.
Electrical Wiring Diagrams, Troubleshooting & Component Locations If values are obtained, also check wiring for intermittent loose terminals and short circuit to B+ and Ground (GND). This
applies especially to sporadic malfunctions.
Use the VAG1594 connector test kit for checking continuity (bridges).
If the measured values only differ slightly from the specifications, clean the sockets and harness connectors of the testers
and adapter leads (using contact spray G 000 700 04) and repeat the test. Before replacing actual components, check
wiring and connections once more. This is especially important if the specification for a resistance test is under 10 .
Pa
ge 21 of 79 Read Measurin
g Value Block
(function 08
)
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play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.SU02.01.8

01-76

Resistance measurement: Select measurement range on VAG1526 (200 ) Test
step VAG
1598/20
sockets Test of
Test requirements
- Additional work stepsSpecified
value Corrective action
1 5 + 33 Left front ABS inlet
valve -N101-, left
front ABS outlet
valve -N102-
2 54 + 26 Right front ABS inlet
valve -N99-, right
front ABS outlet
valve -N100- Electrical wiring
between control module
and hydraulic unit OK 9 22

- Check electrical wiring between
control module and hydraulic unit for
short circuit to Ground (GND) or B+
3 53 + 25 Inlet valve -N134-,
outlet valve -N136-
left-rear Electrical Wiring Diagrams,
Troubleshooting & Component
Locations
4 6 + 34 Inlet valve -N133-,
outlet valve -N135-
right-rear
- If the electrical wiring is OK,
replace the hydraulic unit.
Pa
ge 22 of 79 Read Measurin
g Value Block
(function 08
)
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p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.SU02.01.8

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

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

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

01-89

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