Page 9 of 366
only switch the MIL on after two successive trips with prior cold start and malfunction occurring. This process repeats
continuously. If the malfunction does not occur again within the next 40 engine starts, this sporadic malfunction is
automatically erased.
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ge 9 of 366 On Board Dia
gnostic
(OBD
) - Multi
port Fuel In
jection
(MFI
)
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Page 10 of 366

01-6
The MFI control module differentiates among approx. 150 different malfunctions after evaluating the information, and
stores them until the DTC memory is erased Diagnostic Trouble Code (DTC) table, page 01
-26
.
If possible, the DTC memory should be checked with engine running.
If no malfunction is stored in the DTC memory, do not additionally erase DTC memory with function 05 since the readiness
code (if it has been set) will be erased.
The DTC memory should only be erased with function 05 since the DTC memory is erased immediately with mode 4 even
if the DTC memory was not checked before that.
If a malfunction recognized by the On Board Diagnostic (OBD) is eliminated, the following work steps should be carried
out after that:
- Erase DTC memory
- Stop engine (switch ignition off) and start it again
- Take a test drive
- Carry out automatic test sequence by inserting address word 00 Note:
Every time the DTC memory is erased (both with function 05 and with mode 4), the readiness code is reset.
Pa
ge 10 of 366 On Board Dia
gnostic
(OBD
) - Multi
port Fuel In
jection
(MFI
)
11/22/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
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pair&id=AUDI.B5.FU01.01.1
Page 11 of 366
01-7
VAG 1551/1552 Scan Tool (ST),
connecting and selecting Engine
Electronics address word 01
Fuses for engine electronics OK
Fuel pump relay OK
Ground connections OK page 01
-5
Connecting-m.y. 1996
- Open back seat ash tray (center console) and remove cover for data
link connector.
- Connect VAG 1551/1552 scan tool with adapter cable VAG 1551/3 to
data link connector.
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(OBD
) - Multi
port Fuel In
jection
(MFI
)
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p://127.0.0.1:8080/audi/servlet/Dis
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Page 12 of 366
01-8
Connecting-m.y. 1997
Note:
The DLC is located below the driver's knee bar to
the left of the steering wheel.
All vehicles - Connect VAG1551 or VAG1552 Scan Tool (ST) with VAG1551/3
adapter to Data Link Connector (DLC).
V.A.G On Board Dia
gnostic
(OBD
) HELP
1 - Rapid data transfer2 - Blink code output
Indicated on display1) 1) Operating modes 1 and 2 are displayed alternately.
Notes: If there is no display, check voltage supply for data link connector:
Pa
ge 12 of 366 On Board Dia
gnostic
(OBD
) - Multi
port Fuel In
jection
(MFI
)
11/22/2002 htt
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play?action=Goto&t
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Page 13 of 366
Electrical Wiring Diagrams, Troubleshooting & Component Locations Additional operating instructions can be obtained by using the VAG
1551 scan tool HELP button. The button is used to advance to the next program step.
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) - Multi
port Fuel In
jection
(MFI
)
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Page 14 of 366
01-9
For the function:
02: Check DTC
Memory - Let engine idle, or, crank
engine with starter for at
least 5 seconds without
switching ignition off
03: Output
Diagnostic
Test Mode - Switch ignition on
04: Basic Setting
- Let engine run or switch
ignition on
07: Code Control
Module - Switch ignition on
08: Read
Measuring
Value Block - Let engine run or switch
ignition on
- Switch printer on with PRINT button (indicator
light in the button lights up).
- Press button -1- for "rapid data transfer"
operating mode.
Rapid data transfer
HELP
Insert address word XX
Indicated on display
Note:
After inserting address word 00 and pressing -Q- button to confirm input,
Pa
ge 14 of 366 On Board Dia
gnostic
(OBD
) - Multi
port Fuel In
jection
(MFI
)
11/22/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
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yp
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pair&id=AUDI.B5.FU01.01.1
Page 15 of 366
an automatic test sequence is carried out (checks DTC memory of all
systems with rapid data transfer).
- Press buttons -0- and -1- to insert the "Engine Electronics" address
word 01.
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(OBD
) - Multi
port Fuel In
jection
(MFI
)
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Page 16 of 366

01-10
Rapid data transfer
Q
01 - Engine Electronics
Indicated on display
- Press -Q- button to confirm input.
Rapid data transfer Scan Tool sends address word 01
Indicated on display
_________________________________________________________
Rapid data transfer
HELP
Control module does not answer
If the following is shown on the display:
Notes:
Electrical Wiring Diagrams, Troubleshooting & Component Locations - A list of possible malfunction causes can be printed out by pressing the
HELP button.
Check data link connector/engine control module wiring connection:Engine control module faulty Diagnostic Trouble Code (DTC) table,
page 01
-26
.
Rapid data transfer
HELP
Error in communication link
If the following is shown on the display:
Notes:
Electrical Wiring Diagrams, Troubleshooting & Component Locations
On vehicles with several On Board Diagnostic (OBD) systems, check
wiring connection between the individual systems: For vehicles with only MFI (Engine Electronics) On Board Diagnostic
Pa
ge 16 of 366 On Board Dia
gnostic
(OBD
) - Multi
port Fuel In
jection
(MFI
)
11/22/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU01.01.1