diagram AUDI A4 1995 B5 / 1.G Brakes Output DTM 03 Workshop Manual

01-154

Output Diagnostic Test Mode (DTM)
-
ABS hydraulic pump -
V64-

Indicated on display:
ABS/EDL hydraulic pump -V64- must start running. This is audible.

When you put your foot on the brake pedal you can feel it vibrating. The
brake pedal vibrates because the hydraulic pump generates pressure
pulses in the brake lines. The pressure pulses generate oscillations.
These are directed to the brake pedal and make it vibrate.
The pressure pulses in the brake lines are not sufficient to lock the
wheels.
The hydraulic circuit diagram shows a systematic representation of
an ABS/EDL system. This will give a better understanding of the
various test steps in the output Diagnostic Test Mode (DTM).
shaded components are in action.Thin solid lines represent hydraulic lines or hoses that are not under
pressure. Thick broken lines represent hydraulic lines or hoses working as
suction lines. Thick solid lines represent hydraulic lines or hoses that are under
pressure.
-
Press button.
Pa
ge 7 of 66 Out
put Dia
gnostic Test Mode
(DTM
) (function 03
)
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yp
e=re
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01-169

Connect VAG1598 test box using VAG1598/27
adapter.

- Switch ignition off.

- Connect VAG1598/27 adapter and VAG1598
test box. Disconnect multi-pin connector from
ABS control module -J104-. Connect
VAG1598/27 adapter and VAG1598 test box to
connector of ABS/EDL wiring harness.
The socket designations on the VAG1598 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

Terminal assignment of multi-pin connector at wiring harness / ABS
control module (w/EDL) -J104-
Note:
All terminals omitted here are not occupied at the moment and must not
be connected to other components!
Pa
ge 23 of 66 Out
put Dia
gnostic Test Mode
(DTM
) (function 03
)
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yp
e=re
pair&id=AUDI.B5.SU02.01.13

01-173
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 only 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 28 of 66 Out
put Dia
gnostic Test Mode
(DTM
) (function 03
)
11/20/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.SU02.01.13

01-174
Test table Set measurement range:
voltage test (20 V =)
Test
step VAG
1598
sockets Test of
Test
requirements
- Additional work
steps Specified
value Corrective action
1 19 + 15 Voltage supply to ABS
control module -J104- via
terminal 15 Ignition
switched on. 10.0 - 14.5
V
Electrical Wiring Diagrams,
Troubleshooting & Component
Locations - Check wire from terminal 19 to
Ground (GND).
- Check wire from terminal 15 to
terminal 15.
Pa
ge 29 of 66 Out
put Dia
gnostic Test Mode
(DTM
) (function 03
)
11/20/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.SU02.01.13

01-175

Set measurement range:
voltage test (20 V =)
Test
step VAG
1598
sockets Test of
Test
requirements
- Additional work
steps Specified
value Corrective action
2 16 + 17 Voltage supply of ABS hydraulic unit -
N55- and motor for ABS hydraulic
pump -V64- via terminal 30 at ABS
control module (w/EDL) -J104- Ignition
switched on. 10.0 - 14.5
V - Check wire from terminal
16 to Ground (GND).
16 + 18 10.0 - 14.5
V

Electrical Wiring Diagrams,
Troubleshooting &
Component Locations - Check wiring from
terminals 17 and 18 to B+
(terminal 30) via fuse (60A).
Pa
ge 30 of 66 Out
put Dia
gnostic Test Mode
(DTM
) (function 03
)
11/20/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.SU02.01.13

01-176

Set measurement range:
voltage test (20 V =)
Test
step VAG
1598
sockets Test of
Test requirements
- Additional work
steps Specified
value Corrective action
3 19 + 14 Function of brake
light switch -F- Ignition switched
off
- Check wire from terminal 19 to Ground
(GND).
Brake pedal not
depressed
- Operate brake pedal.0.0 -0.5 V

10.0 - 14.5
V
Electrical Wiring Diagrams,
Troubleshooting & Component Locations

Repair Manual, Brake System, Repair
Group 45
- Check wiring from terminal 14 to
terminal 30 via fuse (10A).
- Check brake light switch -F-
- Adjust brake light switch -F-.
Pa
ge 31 of 66 Out
put Dia
gnostic Test Mode
(DTM
) (function 03
)
11/20/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.SU02.01.13

01-177

Set measurement range:
Resistance measurement (2 k ) Test
step VAG
1598
sockets Test of
Test
requirements
- Additional work
steps Specified
value Corrective action
4
4 + 5
1) 2)
3 + 5
3) Resistance of right
front ABS wheel
speed sensor -G45-
- Check electrical wiring between control
module and wheel speed sensor for open
circuit and for short circuit to Ground
(GND) or B+
5 6 + 7

(all
versions) Resistance of left
front ABS wheel
speed sensor -G47-
Ignition
switched off 400 2300
Electrical Wiring Diagrams,
Troubleshooting & Component Locations - Check harness connectors.
- Move wire during test (loose contact).- Replace the relevant ABS wheel speed
sensor if specified value is not obtained
and the electrical wiring is OK.
1) Assignment of wheel speed sensor terminals for vehicles with Front Wheel Drive (FWD) and equipped with EDL. 2) Assignment of wheel speed sensor terminals for vehicles with All Wheel Drive (AWD) and equipped with EDL. 3) Assignment of wheel speed sensor terminals for vehicles with Front Wheel Drive (FWD) and equipped with ASR.
Pa
ge 32 of 66 Out
put Dia
gnostic Test Mode
(DTM
) (function 03
)
11/20/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.SU02.01.13

01-178

Set measurement range:
Resistance measurement (2 k ) Test
step VAG
1598
sockets Test of
Test
requirements
- Additional work
steps Specified
value Corrective action
6
1 + 3
1)
1 + 2
2) 3) Resistance of right
rear ABS wheel
speed sensor -G44-
- Check electrical wiring between control
module and wheel speed sensor for open
circuits and for short circuit to Ground
(GND) or B+
7 8 + 9

(all
versions) Resistance of left
rear ABS wheel
speed sensor -G46-
Ignition
switched off 400 2300
Electrical Wiring Diagrams,
Troubleshooting & Component Locations - Check harness connectors.
- Move wire during test (loose contact).- Replace the relevant ABS wheel speed
sensor if specified value is not obtained
and the electrical wiring is OK.
1) Assignment of wheel speed sensor terminals for vehicles with Front Wheel Drive (FWD) and equipped with EDL. 2) Assignment of wheel speed sensor terminals for vehicles with All Wheel Drive (AWD) and equipped with EDL. 3) Assignment of wheel speed sensor terminals for vehicles with Front Wheel Drive (FWD) and equipped with ASR.
Pa
ge 33 of 66 Out
put Dia
gnostic Test Mode
(DTM
) (function 03
)
11/20/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.SU02.01.13

01-180

Function test: ABS/EDL warning light -K47-
Test step
VAG
1598
sockets Test of
Test
requirements
- Additional work
steps Specified value
Corrective action
8

Continuation: - Function of
ABS/EDL
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/EDL warning light does not come
on, check voltage of electrical system and
test wiring from terminal 21 of ABS control
module -J104- to instrument cluster for
short circuit to Ground (GND).
- The ABS/EDL warning lamp does not
switch off after 2 seconds. The red "brake
system malfunction" symbol lights up after
2 seconds. Check wire from terminal 21 of
ABS control module -J104- to instrument
cluster for short circuit to B+ and open
circuit.

Repair Manual, Electrical Equipment,
Repair Group 90.
- If vehicle voltage and wire from terminal
21 of ABS control module -J104- to
instrument cluster are OK there is a
malfunction in instrument cluster, LED or
bulb malfunctioning.
Pa
ge 35 of 66 Out
put Dia
gnostic Test Mode
(DTM
) (function 03
)
11/20/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.SU02.01.13

01-184

Function test: Traction control indicator light -K86-, only installed on vehicles equipped with ASR
Test step
VAG
1598
sockets Test of
Test
requirements
- Additional work
steps Specified value
Corrective action
10

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 20 of ABS control
module -J104- to instrument cluster for
short circuit to B+ and open circuit.
- If traction control indicator lights
continuously, test wire from terminal 20
of ABS control module -J104- to
instrument cluster for short circuit to
Ground (GND).

Repair Manual, Electrical Equipment,
Repair Group 90; instrument cluster.
- If vehicle voltage and wire from
terminal 20 of ABS control module -
J104- to instrument cluster are OK
there is a malfunction in instrument
cluster, LED or bulb malfunctioning.
Pa
ge 39 of 66 Out
put Dia
gnostic Test Mode
(DTM
) (function 03
)
11/20/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.SU02.01.13