AUDI A6 1998 C5 / 2.G ATQ Engine Motronic On Board Diagnostic User Guide

01-9

VAS 5051 vehicle diagnostic, testing
and information system orVAG1551
Scan Tool (ST), connecting and
selecting functions


Test requirements:

Fuses for engine electronics OK

Electrical Wiring Diagrams, Troubleshooting &
Component Locations binder

Fuel Pump (FP) OK, checking Page 24
-
49
.

Battery voltage at least 12.7 V
Ground (GND) connections at engine and
transmission OK

Procedure

Note: - Connect VAS5051 tester to vehicle with VAS5051/1 diagnostic wire.
Alternately, VAG1551 Scan Tool (ST) can also be attached using
VAG1551/3B cable.
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Data Link Connector (DLC) is located in front left knee bolster.
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01-10

WARNING!

Observe safety precautions Page 01
-8 .

Note:
The following description only explains
implementation of On Board Diagnostic using
VAG1551 Scan tool.
When using the VAS5051 tester, observe the
tester's instructions for use V.A.G - ON BOARD DIAGNOSTIC
HELP
1 - Rapid data transfer 1)2 - Blink code output 1
)

Indicated on display: 1) Operating modes 1 and 2 are displayed alternately
Note:
If nothing appears in display:
- Perform troubleshooting procedure after "troubleshooting procedure leak
test":
Electrical Wiring Diagrams, Troubleshooting & Component Locations
binder
Depending on desired function Table "Selectable functions", page
Page 01
-14
:
- Switch ignition on.
or
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- Start engine.
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01-11

- Press -Print- button to turn on Scan Tool (ST)
printer. Indicator lamp in button must light up.

- Press button 1 to select "Rapid data transfer"
operating mode 1. Rapid data transfer
HELP
Insert address word XX

When indicated on display:
Note:
The address word 00 initiates the automatic test sequence, i.e. it results in
a DTC check on all OBD capable systems in the vehicle via rapid data
transfer.
- Press buttons -0- and -1- to select "engine electronics" and press -Q-
button to confirm input.
3B0907551BA
2.8l V6/5V
G
0003
Codin
g 07251
WSC 12345

VAG1551 Scan Tool (ST) display indicates control module identification,
e.g.:
Note:
Control module identification can be printed by pressing the PRINT key of
the VAG1551 scan tool.
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01-12

Control module identification (example)

3B0907551
BA part number; allocation
Parts Catalog 2.8 LEngine displacement V6/5VConstruction style of engine (V
engine, 6 cylinder, 5 valves) "G" i.e. no
indication Vehicle with or without cruise
control system 0003Data version (software
version) of control module Coding
07251 Control module coding WSC 12345 Factory identification of
VAG1551, with which the last
coding was performed

-
Press button.
Rapid data transfer
HELP
Select function XX

Indicated on display (function selection):
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01-13

Notes:

It will be possible to display the control module
identification again after pressing buttons -0-
and -1- to select "Check Control Module
Versions" and confirming with the -Q- button.
Rapid data transfer
HELP
Control module does not answer

When indicated on display:
Rapid data transfer
HELP
K-wire not switchin
g to Ground

- Perform troubleshooting procedure after "troubleshooting procedure leak
test":
Electrical Wiring Diagrams, Troubleshooting & Component Locations
binder
Rapid data transfer
HELP
K-wire not switchin
g to B+

Rapid data transfer
HELP
Error in communication link

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01-14
Selectable functions VAS 5051 vehicle diagnostic, testing and information
system or VAG1551 Scan Tool (ST) Ignition
on,
engine
off Engine running
at idle Vehicle in drive
mode page
Address words
01 Engine electronics Yes Yes Yes Page
01
-9
00 Automatic test sequence Yes Yes Yes Page
01
-11

Functions
01 Check Control Module Versions Yes Yes Yes Page
01
-13

02 Check DTC Memory No Yes Yes Page
01
-15

03 Output Diagnostic Test Mode (DTM) Yes No No Page
01
-56

04 Basic Setting Yes Yes Yes Page
01
-66

05 Erase DTC Memory Yes Yes Yes Page
01
-15

06 End Output Yes Yes Yes Page
01
-17

07 Code Control Module Yes No No Page
01
-71

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08 Read Measuring Value Block Yes Yes Yes Page
01
-74

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