1997 AUDI A4 ignition

28-32

Control module voltage supply,
checking


Test requirements:

Fuse for Engine Control Module (ECM) OK

Electrical Wiring Diagrams, Troubleshooting &
Component Locations

Battery voltage at least 11 V
Generator OK

- Connect test box VAG1598/31 to wiring harness
for engine control module. Do not connect to the
engine control module itself. Page 24
-20
.

- Switch ignition on.

Note:

The B+ voltage supply for the engine control
module comes via terminal 3 (terminal 15) and
terminal 62 (terminal 30).

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pair&id=AUDI.B5.FU04.28.1

28-35
Measuring value blocks for ignition timing angle retard Display Group 20 -Ignition- Knock control

Driving mode
Read measuring value block 20

Indicated on display

xx.x KW
xx.x KW
xx.x KW
xx.x KW



1 2
3 4
Display fields
Specified value
Evaluation


Ignition timing retard via knock control:
cylinder 4 0...12 KW
(crankshaft
angle)
Page 28
-40




Ignition timing retard via knock control:
cylinder 3
0...12 KW
(crankshaft
angle)
Page 28
-40



Ignition timing retard via knock control: cylinder 2
0...12 KW
(crankshaft
angle)
Page 28
-40



Ignition timing retard via knock control: cylinder 1
0...12 KW
(crankshaft
angle)
Page 28
-40


Note:
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play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU04.28.1

The displayed digit values in display fields 1 to 4 reflects the actual "ignition timing retard" via knock control from the individual
cylinders. The ignition timing retard occurs via KW (crankshaft angle).
Pa
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11/22/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU04.28.1

28-36

Display Group 21 -Ignition- Knock control

Driving mode
Read measuring value block 21

Indicated on display

xx.x KW
xx.x KW



1 2
3 4
Display fields
Specified value
Evaluation











Ignition timing retard via knock control: cylinder 6
0...12 KW
(crankshaft angle)
Page 28
-40


Ignition timing retard via knock control: cylinder 5
0...12 KW
(crankshaft angle)
Page 28
-40

Note:
The displayed digit values in display fields 1 and 2 reflects the actual "ignition timing retard" via knock control from the
individual cylinders. The ignition timing retard occurs via KW (crankshaft angle).
Pa
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11/22/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU04.28.1

28-37

Display Group 22 -Ignition- Knock control

Driving mode
Read measuring value block
22
Indicated on display

xx.x RPM x.x %
xx.x KW
xx.x KW



1 2
3 4
Display fields
Specified value
Evaluation


Ignition timing retard via knock control:
cylinder 2 0...12 KW
(crankshaft
angle)
Page 28
-40




Ignition timing retard via knock control:
cylinder 1
0...12 KW
(crankshaft
angle)
Page 28
-40



Engine load 15 - 175 %

Engine speed RPM
750 - 6800 RPM

Note:
The displayed digit values in display fields 3 and 4 reflects the actual "ignition timing retard" via knock control from cylinders 1
and 2. The ignition timing retard occurs via KW (crankshaft angle).
Pa
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11/22/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU04.28.1

28-38

Display Group 23 -Ignition- Knock control

Driving mode
Read measuring value block
23
Indicated on display

xx.x RPM x.x %
xx.x KW
xx.x KW



1 2
3 4
Display fields
Specified value
Evaluation


Ignition timing retard via knock control:
cylinder 4 0...12 KW
(crankshaft
angle)
Page 28
-40




Ignition timing retard via knock control:
cylinder 3
0...12 KW
(crankshaft
angle)
Page 28
-40



Engine load 15 - 175 %

Engine speed RPM
750 - 6800 RPM

Note:
The displayed digit values in display fields 3 and 4 reflects the actual "ignition timing retard" via knock control from cylinders 3
and 4. The ignition timing retard occurs via KW (crankshaft angle).
Pa
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ystem, checkin
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11/22/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU04.28.1

28-39

Display Group 24 -Ignition- Knock control

Driving mode
Read measuring value block
24
Indicated on display

xx.x RPM x.x %
xx.x KW
xx.x KW



1 2
3 4
Display fields
Specified value
Evaluation


Ignition timing retard via knock control:
cylinder 6 0...12 KW
(crankshaft
angle)
Page 28
-40




Ignition timing retard via knock control:
cylinder 5
0...12 KW
(crankshaft
angle)
Page 28
-40



Engine load 15 - 175 %

Engine speed RPM
750 - 6800 RPM

Note:
The displayed digit values in display fields 3 and 4 reflects the actual "ignition timing retard" via knock control from cylinders 5
and 6. The ignition timing retard occurs via KW (crankshaft angle).
Pa
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11/22/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU04.28.1

28-40
Evaluation display groups 20/21/22/23/24, - Ignition timing angle retard Indicated on display
Malfunction cause
Corrective action
All cylinders greater
than 12 KW
Knock sensor faulty- Check knock sensor Page 28
-41
.


Corroded connection

Knock sensor incorrect
tightening torque - Loosen and tighten knock sensor with 20 Nm (15 ft lb)

Components on engine
loose - Tighten components

Low fuel grade- Change fuel grade
One cylinder deviates
clearly from others Corroded connection- Check knock sensor Page 28
-41
.


Engine damage
Repair Manual, 2.7 Liter V6 5V BiTurbo Engine Mechanical, Engine
Code(s): APB, Repair Group 15, Cylinder head removing, check compression pressure
- Check compression pressure:


Components on engine
loose - Tighten components
Pa
ge 45 of 64 I
gnition s
ystem, checkin
g
11/22/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU04.28.1