wiring AUDI A4 1995 B5 / 1.G Brakes Read Mesure Value Block Workshop Manual

01-61


Read Measuring Value Block
(function 08)
The control module can transmit measured
values to the VAG1551 Scan Tool (ST). These
measured values provide information about the
operational status of the system and the sensors
connected to it. In many cases the data supplied
can be used to troubleshoot and repair
malfunctions. The measured values from the
Bosch 5.0 series are contained in three display
groups, which can be accessed via their display
group numbers.

- Connect the VAG1551 Scan Tool (ST) and
select "Brake Electronics" via address word 03
page 01
-4 .

Notes:

When the printer is switched on, the contents of
the display will be printed out on the scan tool
log.
When reading the measuring value block, also
check wiring and connectors for loose
terminals.

- Check the control module version page 01
-52

and press the button.
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g Value Block
(function 08
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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.
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g Value Block
(function 08
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01-69


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.
Multi-pin harness connector for ABS control module -J104- in proper
condition, with no bent, broken or corroded terminals. Replace any
damaged terminals using VAS1978 wiring repair kit. 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
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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
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g Value Block
(function 08
)
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01-72
Terminal assignment of multi-pin connector for wiring harness / ABS control module (w/EDL) -J104- Terminal
Wire connection to component ...
1
Voltage supply, terminal 15 2
Hydraulic unit; activation of ABS return flow pump relay -J105- 3
Hydraulic unit; left front traction control switch-over valve -N168- (secondary piston circuit) 4
Hydraulic unit; left front traction control outlet valve -N169- (secondary piston circuit) 5
Hydraulic unit; left front ABS inlet valve -N101- 6
Hydraulic unit; right rear ABS inlet valve -N133- 7
Hydraulic unit; activation of ABS return flow pump relay -J105- 9
Left front ABS wheel speed sensor -G47-
for vehicles with Front Wheel Drive (FWD) and ABS/EDLfor vehicles with Front Wheel Drive (FWD) and ABS/EDL/ASR
10
Left front ABS wheel speed sensor -G47- 11
Right rear ABS wheel speed sensor -G44- 12
Left rear ABS wheel speed sensor -G46- 13
Left rear ABS wheel speed sensor -G46- 14
Right front ABS wheel speed sensor -G45- 15
Right front ABS wheel speed sensor -G45-
for vehicles with Front Wheel Drive (FWD) and ABS
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g Value Block
(function 08
)
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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
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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
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g Value Block
(function 08
)
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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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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
)
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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
)
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