1998 VOLKSWAGEN BORA brake

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List of selectable display group numbers
Display group number
Display zone
Designation
001 1 Wheel speed at left front wheel sensor (km/h)
2 Wheel speed at right front wheel sensor (km/h)
3 Wheel speed at left rear speed sensor (km/h)
4 Wheel speed at right rear speed sensor (km/h)
002 1 Wheel speed at left front speed sensor (km/h)
2 Wheel speed at right front wheel sensor (km/h)
3 Wheel speed at left rear speed sensor (km/h)
4 Wheel speed at right rear speed sensor (km/h)
003 1 Brake light switch
2 Vacant
3 Vacant
4 Vacant
Стр. 44из 81 ABS ITT Mk 20 IE On Board Diagnostic (OBD) program

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Checking brake light switch for ABS and
ABS/EDL function

Display group number 003

- Press keys 0, 0 and 3

- Confirm entry with key Q.
Read measured value block
3
1 2 3 4
There are always 4 display zones -arrows-
in the measured value block. Decoding the
individual values in display zones 1 to 4 can
be read from the following tables.
Read measured value block 3
0
Indicated on display
Press C key for the next display group
number entry.
If the key is pressed, keys 0 and 8 for
work sequence "Read measured value
block" must be pressed again afterwards to
regain entry.
Стр. 50из 81 ABS ITT Mk 20 IE On Board Diagnostic (OBD) program

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Read measured value block
3 Display group number: 003
0
Indicated on display

Vacant

Vacant

Vacant

Brake light switch:
If despite pressed foot brake a -0-, or not pressed foot brake a -1- is displayed on the
V.A.G 1551 display; perform test step No. 4 of Electrical check, Page 01
-102 .
There is also a possibility that the brake light switch has not been correctly adjusted.
Adjusting brake light switch, Page 01
-131 .
0 Brake pedal not depressed
1 Brake pedal depressed
Стр. 51из 81 ABS ITT Mk 20 IE On Board Diagnostic (OBD) program

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Output Diagnostic Test Mode (DTM)

Note:

All functions which could previously be
performed with V.A.G 1551 can also be
performed with the tester VAS 5051.

The pump motor and the correct functioning of
the hydraulic circuits (allocation of brake lines to
wheel cylinders and function of valves) can be
checked via the output DTM for interchange or
leaks.

The vehicle must be raised until all wheels are
free to turn. (2nd mechanic required to rotate
wheels)

The -C- key can be used to exit the test
sequence at any time.

After depressing the brake pedal several times
the vacuum in the brake booster will be
exhausted. Therefore more pressure must be
applied to the brake pedal in order to attain the
same fluid pressure in brake system, as that
attained with vacuum.

When vacuum in brake booster is exhausted
wheels may not lock; start engine and build-up
vacuum in brake booster.
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- Connect V.A.G 1551 Scan Tool.

- Switch ignition on.

- Press key -1- for "Rapid data transfer" operating
mode.

- Select brake electronics (address word 03);
Page 01
-23
Rapid data transfer Q
03 - Brake electronics Indicated on display
Note:
During the next work steps the ABS warning light -
K47- flashes. - Confirm entry with key Q.
- Read off control module version in V.A.G 1551
display.
-
Press key.
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Rapid data transfer HELP
Select function XX Indicated on display
- Press keys 0 and 3
Rapid data transfer Q
03 - Out
put Diagnostic Test Mode
Indicated on display
- Confirm entry with key Q.
ABS hydraulic pump -V64- must run.
Output Diagnostic Test Mode
-
ABS hydraulic pump - V64
Indicated on display
-
Press key.
Output Diagnostic Test Mode
-
Operate brakes
Indicated on display
- Operate brake pedal.
-
Press key.
Output Diagnostic Test Mode
-
IFL: 0V OFL: 0V Wheel FL locked
Indicated on display
Note:
If the wheel does not lock, there is a
possibility that there is a malfunction in the
mechanical/hydraulic part of the brake
system. - Indicate to 2nd mechanic which wheel
requires turning by hand.
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-
Press key.
Output Diagnostic Test Mode
-
IFL: VBAT OFL: 0V Wheel FL locked
Indicated on display
If the brake pedal gives, there is a
malfunction in the hydraulic unit. In this
case the hydraulic unit must be replaced.
Repair Manual, Brake System, Repair
Group 45; Hydraulic unit, brake
booster/brake master cylinder - Assembly
overview; Removing and installing control
module and hydraulic unit -
Press key.
ABS hydraulic pump -V64- must run.
Brake pedal must not give.
Output Diagnostic Test Mode
-
IFL: VBAT OFL: VBAT Wheel FL free
Indicated on display
Note:
If the wheel locks there is a possibility that
the brake lines to the wheel
calipers/cylinders have been interchanged. - Indicate to 2nd mechanic which wheel
requires turning by hand.
Стр. 58из 81 ABS ITT Mk 20 IE On Board Diagnostic (OBD) program

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-
Press key.
ABS hydraulic pump -V64- no longer
runs.
Output Diagnostic Test Mode
-
IFL: VBAT OFL: 0V Wheel FL free
Indicated on display
If the brake pedal does not give, there is a
malfunction in the hydraulic unit. In this
case the hydraulic unit must be replaced.
Repair Manual, Brake System, Repair
Group 45; Hydraulic unit, brake
booster/brake master cylinder - Assembly
overview; Removing and installing control
module and hydraulic unit -
Press key.
Brake pedal must give perceptibly
Output Diagnostic Test Mode
-
IFL: 0V OFL: 0V Wheel FL locked
Indicated on display
Note:
If the wheel does not lock, there is a
possibility that there is a malfunction in the
mechanical/hydraulic part of the brake
system. - Indicate to 2nd mechanic which wheel
requires turning by hand.
Стр. 59из 81 ABS ITT Mk 20 IE On Board Diagnostic (OBD) program