brake AUDI A4 1998 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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01-65
Test table: display group 2 Read measuring value block
2
Indicated on display
0 or 1
0 or 1

0 or 1
0 or 1



ABS solenoid valve relay:
For vehicles with Front Wheel Drive (FWD), the display shifts one field toward
left.
0 not permitted during "Read measuring value block", the relay was not
activated during "ignition on".
- Carry out "Electrical test", step 11 page 01
-68
.
1 specified value, relay was activated by ABS control module -J104- during
ignition on.

Voltage at motor for ABS return flow pump:
For vehicles with Front Wheel Drive (FWD), the display shifts one field toward left.

0 specified value, there is no voltage at the motor for the ABS return flow pump. 1 not permitted during "Read measuring value block", there is voltage at the motor for the
ABS return flow pump.
- Carry out "Electrical test", step 12 page 01
-68
.

Brake light switch: Additional signal only for
All Wheel Drive (AWD):
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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
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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.
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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-
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g Value Block
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01-80

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 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. Repeat test step 13.
- If all wheels are blocked, inlet valve is
malfunctioning DTC table page 01
-98
,
DTC 00257.

- Remove bridge 5 +
28.
The left-
front wheel
remains
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g Value Block
(function 08
)
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locked.

- Release brake pedal.
1) This test step requires two technicians.
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g Value Block
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01-81

Function test
Test
step VAG
1598/20
sockets Test of
Test requirements
- Additional work stepsSpecified
value Corrective action
14
1)
Bridge
1 + 2,
28 + 37 Inlet valve -N99-
and front right
brake line
connection
Ignition on

- for vehicles with
automatic
transmission, engage
neutral position "N"
- Bridge terminals 54 +
28
- Depress brake pedal
and hold.





Right 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. Repeat test step 14.
- If all wheels are blocked, inlet valve is
malfunctioning DTC table page 01
-98
,
DTC 00259.

- Remove bridge 54 +
28.
The right-
front wheel
remains
Pa
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g Value Block
(function 08
)
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locked.

- Release brake pedal.
1) This test step requires two technicians.
Pa
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g Value Block
(function 08
)
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01-82

Function test
Test
step VAG
1598/20
sockets Test of
Test requirements
- Additional work stepsSpecified
value Corrective action
15
1)
Bridge
1 + 2,
28 + 37 Inlet valve -
N134- and rear
left brake line
connection
Ignition on

- for vehicles with
automatic
transmission, engage
neutral position "N"
- Bridge terminals 53 +
28
- Depress brake pedal
and hold.





Left rear
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. Repeat test step 15.
- If all wheels are blocked, inlet valve is
malfunctioning DTC table page 01
-98
,
DTC 00274.

- Remove bridge 53 +
28.
The left-
rear wheel
remains
Pa
ge 31 of 79 Read Measurin
g Value Block
(function 08
)
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e=re
pair&id=AUDI.B5.SU02.01.8