check engine VOLKSWAGEN JETTA 1998 Service Manual

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Read measured value block
6 Display group number: 006
0.0m/s
2

Indicated on display (example)

Vacant

Vacant

Vacant

Longitudinal acceleration sensor:
1)

Specification when vehicle is stationary:+/- 1.5m/s2

Specification when accelerating forwards: The values increase steadily.

Specification when accelerating in reverse: The values increase steadily
with a negative sign (-).

Check longitudinal acceleration sensor -G251- Page 01-259
Perform electrical check Page 01-288
1) When performing a test drive where the V.A.G 1551 scan tool or tester VAS 5051 is
connected and in diagnosis or read measured value block mode there is no ABS regulation.
The ABS warning light does not light up. The OBD of ABS control module (w/EDL) -J104- is
terminated when exceeding a speed of 20 km/h (13 mph).
Стр. 100из 129 On Board Diagnostic (OBD), performing

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Checking longitudinal acceleration sensor -
G251-
1)

- Remove longitudinal acceleration sensor -G251-
without pulling off connector.
Repair Manual, Brake System, Repair Group
45

Note:
All functions that have so far been carried out
with V.A.G 1551 can now also be carried out with
the tester VAS 5051.

- Connect V.A.G. 1551 scan tool.
The longitudinal acceleration sensor -G251- can
be checked with the help of function "Read
measured value block", display group 006.
Read measured value block
6
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-off
from the following tables.
Read measured value block
6
0.0m/s2
Indicated on display: e.g. (vehicle stationary)
1) For 4MOTION vehicles only
Стр. 101из 129 On Board Diagnostic (OBD), performing

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Checking data bus wiring

Display group number 125

- Press keys 1, 2 and 5

- Confirm entry with key Q.
Read measured value block
125
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-off from the
following tables.
Read measured value block 125
Engine 1 St.ang. 1 4WD 1 Gear.1
Indicated on display: (vehicle stationary)
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. 103из 129 On Board Diagnostic (OBD), performing

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Display group number 0691) is required to
perform a zero compensation of longitudinal
acceleration sensor -G251- Page 01
-281 .
Display group number 0932) is required to
perform a driving test Page 01
-284. It serves
to check the plausibility of the signals from the
steering angle sensor -G85-, Sensor for
transverse acceleration -G200- Sender for
Rotation Rate -G202- and sender 1 for brake
booster -G201-.
When the ABS control module (w/EDL) -J104- is
replaced, a zero compensation must be
performed for the following components:

Sensor for transverse acceleration -G200-.

Steering angle sensor -G85-.

Sender 1 for brake booster -G201-.

Longitudinal acceleration sensor -G251-.1)
When the individual sensors or sensors are
changed, a zero compensation must only be
carried out for the changed component.

1) For 4MOTION vehicles only

2) For ABS/EDL/ASR/ESP and
ABS/EDL/ASR/ESP 4MOTION only
Стр. 107из 129 On Board Diagnostic (OBD), performing

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Rapid data transfer HELP
Enter address word XX Indicated on display:
- Press keys 0 and 4. (The function
"Initiating basic setting" is selected with
04).
Rapid data transfer Q
04 - Basic settin
g
Indicated on display:
- Confirm entry with key Q.
Basic setting HELP
Enter displa
y group number XXX
Indicated on display:
- Press keys 0, 4 and 0
- Confirm entry with key Q.
ABS warning light flashes.
Basic setting 40 Indicated on display:
- The longitudinal acceleration sensor -
G251- is now switched off.
- After completing the checks, reactivate
the longitudinal acceleration sensor -
G251- by switching the ignition off and
on again, once.
Стр. 112из 129 On Board Diagnostic (OBD), performing

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Display group number 60: zero compensation
of steering angle sensor -G85-

Note:

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

- Connect V.A.G 1551 scan tool and select
(address word 03) brake electronics control
module with ignition switched on; Page 01
-
163 .

- Start engine.

- Carry out a short test drive over a flat and level
surface. Drive straight-ahead and not faster then
20 km/h (12.5 mph) and observe the following
points:

If the steering wheel is not in the centered
position when driving straight ahead, the
steering must be corrected within the
framework of an alignment check.
Repair Manual, Suspension, Wheels,
Steering, Repair Group 44; Vehicle alignment.
Стр. 113из 129 On Board Diagnostic (OBD), performing

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If the steering wheel is in the straight ahead
position during the test drive, stop the vehicle
while still driving straight ahead.

- Check specifications with help of function 08
"Read measured value block" Page 01
-240 ,
Display group number 004.

Make sure steering wheel does not moved.
Do not turn ignition switch off!

First perform function 11 "Login procedure"
successfully using V.A.G 1551 scan tool
Page 01
-287
Rapid data transfer HELP
Enter address word XX Indicated on display:
- Press keys 0 and 4. (The function "Initiating
basic setting" is selected with 04).
Rapid data transfer Q
04 - Basic settin
g
Indicated on display:
- Confirm entry with key Q.
Стр. 114из 129 On Board Diagnostic (OBD), performing

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- or:
Basic setting 60 OFF <4-ON>
Compens. not poss.
12. If this appears in the display, the measured
values for the zero compensation are not
within the allowed tolerance.
1. Check DTC memory (Function 02)
2. Erase DTC memory (Function 05)
3. End output (Function 06)
4. Switch off ignition.
5. Switch on ignition.
6. Perform zero compensation again. - Check specifications with help of function
08 "Read measured value block"
Page 01
-240 , Display group number
004.
-
Press key.
Rapid data transfer HELP
Enter address word XX Indicated on display:
- Press keys 0 and 6, this ends the output.
Rapid data transfer Q
06 - End output Indicated on display
ABS and ESP warning lights light up for
approx. 2 seconds.
Стр. 116из 129 On Board Diagnostic (OBD), performing

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Display group number 63: zero compensation
of Sensor for transverse acceleration -G200-

Note:
All functions which could previously be
performed with V.A.G 1551 can now also be
carried out with the tester VAS 5051.

Position vehicle on a flat level surface.

- Connect V.A.G 1551 scan tool and select
(address word 03) brake electronics control
module with ignition switched on; Page 01
-
163 .

- Check specifications with help of function 08
"Read measured value block" Page 01
-240 ,
Display group number 004.
First perform function 11 "Login procedure"
successfully using V.A.G 1551 scan tool
Page 01
-287
Rapid data transfer HELP
Enter address word XX Indicated on display:
- Press keys 0 and 4. (The function "Initiating
basic setting" is selected with 04).
Стр. 117из 129 On Board Diagnostic (OBD), performing

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Rapid data transfer Q
04 - Basic settin
g
Indicated on display:
- Confirm entry with key Q.
Basic setting HELP
Enter dis
play group number XXX
Indicated on display:
- Press keys 0, 6 and 3
- Confirm entry with key Q.
ABS warning light flashes.
Basic setting 63 OFF <4-ON>
Compens. OK. 0.6m/s2 And then the display shows e.g.:
Function is unknown or cannot be
-
performed at moment
If this display appears the login procedure
has not been performed successfully.
- or:
Basic setting 63 OFF <4-ON>
Com
pens. not poss. 5.0m/s2
If this appears in the display, the measured
values for the zero compensation are not
within the allowed tolerance.
- Check specifications with help of function
08 "Read measured value block"
Page 01
-240 , Display group number
004.
Стр. 118из 129 On Board Diagnostic (OBD), performing