ignition AUDI A4 1999 B5 / 1.G Brakes Read Mesure Value Block Workshop Manual

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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g Value Block
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01-68

Electrical testing


If the On Board Diagnostic (OBD) sequence
does not provide any indication of the source of
the malfunction, work through all of the
electrical test steps.
If the OBD sequence identifies the source of the
malfunction, only carry out the test steps
recommended in the DTC table (specific
testing).

Test requirements
The "Automatic Test Sequence" was carried
out and it was determined that the
Transmission Control Module (TCM) and
Engine Control Module (ECM) only contain
DTCs relating to ABS.

- Connect the VAG1551 Scan Tool (ST) and
select the address word 00 with ignition
switched on;

- After completing electrical test, check and
erase DTC memories of Transmission Control
Module (TCM) and Engine Control Module
(ECM).
Pa
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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
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)
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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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01-80

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
Pa
ge 27 of 79 Read Measurin
g Value Block
(function 08
)
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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
ge 29 of 79 Read Measurin
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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01-83

Test
step VAG
1598/20
sockets Test of
Test requirements
- Additional work stepsSpecified
value Corrective action
16
1)
Bridge
1 + 2,
28 + 37 Inlet valve -
N133- and rear
right brake line
connection
Ignition on

- for vehicles with
automatic
transmission, engage
neutral position "N"
- Bridge terminals 6 +
28
- Depress brake pedal
and hold.





Right 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 16.
- If all wheels are blocked, inlet valve is
malfunctioning DTC table page 01
-98
,
DTC 00273.

- Remove bridge 6 +
28.
The right-
rear wheel
remains
locked.
Pa
ge 33 of 79 Read Measurin
g Value Block
(function 08
)
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01-84

Function test and check for proper seal
Test
step VAG
1598/20
sockets Test of
Test requirements
- Additional work stepsSpecified value
Corrective action
17 Bridge
1 + 2,
7 + 37,
37 + 28
ABS return
flow pump -
V39-
Left front
traction
control
switch-over
valve -N168-
Left front
traction
control outlet
valve -N169- Repair Manual,
Brake System, Repair Group 47
- Connect VAG1310A
pressure gauge to front
left brake caliper and
bleed.
- Bridge terminals 3 +
28
Repair Manual, Brake System,
Repair Group 45
- ABS return flow pump
malfunctioning, replace ABS
hydraulic unit -N55-


Pressure
relief valve in
ABS hydraulic
unit -N55-
Left front ABS
outlet valve -
N102- - Switch on ignition for
max. 10 seconds and
switch off again.
Left front
traction control
switch-over
valve -N168-
switched ABS return
flow pump -
V39- runs Pressure on
pressure - Check left front traction control
switch-over valve -N168- and left
front traction control outlet valve -
N169- via resistance test test steps
5 + 6. Replace ABS hydraulic unit -
N55- if malfunctioning.
Pa
ge 35 of 79 Read Measurin
g Value Block
(function 08
)
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01-85

Function test and check for proper seal
Test step
VAG
1598/20
sockets Test of
Test requirements
- Additional work
steps Specified value
Corrective action
17

Continuation:

Right rear
ABS
outlet
valve -
N135- - Bridge terminals 4 +
28
- Switch on ignition for
max. 10 seconds and
switch off again.
Front Wheel Drive
(FWD):
170 25 bar
All-Wheel Drive
(AWD), pressure
regulation (ABS):
90 25 bar
Left front
traction control
outlet valve -
N169- switchedPressure
increases on
pressure
gauge:
- Pressure relief valve and/or left
front ABS outlet valve -N102-
and/or right rear ABS outlet valve
-N135- malfunctioning. Replace
ABS hydraulic unit -N55-.

- Remove VAG1310A
pressure gauge and
bleed brakes All Wheel Drive
(AWD), throttle
valve regulation:
170 25 bar

Pa
ge 37 of 79 Read Measurin
g Value Block
(function 08
)
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