1995 AUDI A4 ABS

for vehicles with Front Wheel Drive (FWD) and ABS/EDLfor vehicles with Front Wheel Drive (FWD) and ABS/EDL (ABS pressure regulation)
Pa
ge 16 of 79 Read Measurin
g Value Block
(function 08
)
11/20/2002 htt
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yp
e=re
pair&id=AUDI.B5.SU02.01.8

01-73

Terminal
Wire connection to component ...
18
Engine Control Module (ECM); MMD signal (Masked Misfire Diagnostic)
for vehicles with Front Wheel Drive (FWD) and ABS/EDL/ASR, the SET signal (Specified Engine Torque) is
also transmitted via this wiring harness.
19
Hydraulic unit; control wire for ABS return flow pump -V39- 20
Engine Control Module (ECM); Engine RPM
for vehicles with Front Wheel Drive (FWD) and ABS/EDL/ASR
25
Hydraulic unit; Left rear ABS outlet valve -N136- 26
Hydraulic unit; Right front ABS outlet valve -N100- 27
Hydraulic unit; right front traction control outlet valve -N167- (primary piston circuit) 28
Ground (GND) terminal 31 (ABS control module -J104-) 29
Ground (GND) terminal 31 (ABS control module -J104-) 31
Instrument cluster; activation of traction control indicator light
for vehicles with Front Wheel Drive (FWD) and ABS/EDL/ASR
32
Instrument cluster; ABS/EDL warning light activation (active) 33
Hydraulic unit; Left front ABS outlet valve -N102- 34
Hydraulic unit; Right rear ABS outlet valve -N135- 35
Left front ABS wheel speed sensor -G47-
for vehicles with All Wheel Drive (AWD) and ABS/EDL
Pa
ge 17 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

36
Left front ABS wheel speed sensor -G47-
for vehicles with Front Wheel Drive (FWD) and ABS
Pa
ge 18 of 79 Read Measurin
g Value Block
(function 08
)
11/20/2002 htt
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play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.SU02.01.8

01-74

Terminal
Wire connection to component ...
37
Hydraulic unit; activation of ABS solenoid valve relay -J106- 38
Right rear ABS wheel speed sensor -G44- 42
Right front ABS wheel speed sensor -G45-
for vehicles with Front Wheel Drive (FWD) and ABS/EDL/ASR for vehicles with All Wheel Drive (AWD) and ABS/EDL (throttle valve regulation)
44
Traction control (ASR) button
for vehicles with Front Wheel Drive (FWD) and ABS/EDL/ASR
45
TI (Transmission Influence)
for vehicles with Front Wheel Drive (FWD) and ABS/EDL/ASR
46
K-wire 47
Engine Control Module (ECM); AET (Actual Engine Torque)
for vehicles with Front Wheel Drive (FWD) and ABS/EDL/ASR
47
Brake light switch -F-
for vehicles with All Wheel Drive (AWD) and ABS/EDL
48
Brake light switch -F- 50
Battery + (terminal 30) 53
Hydraulic unit; left rear ABS inlet valve -N134-
Pa
ge 19 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

54
Hydraulic unit; right front ABS inlet valve -N99- 55
Hydraulic unit; right front traction control switch-over valve -N166- (primary piston circuit)
Pa
ge 20 of 79 Read Measurin
g Value Block
(function 08
)
11/20/2002 htt
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play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.SU02.01.8

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
)
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

01-76

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
)
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

01-77

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