AUDI A6 1997 C5 / 2.G ATQ Engine Ignition System Checking Service Manual

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Display fields

1 2 3 4
Display group 021: Ignition -knock control in driving operation
Display
xx.x KW
xx.x KW


Indicated
Ignition angle retardation cylinder 5 via
knock control
Knock sensor control Ignition angle retardation cylinder 6 via
knock control
Knock sensor control

Specified
value 0 to 12 KW
0 to 12 KW


Notes Evaluation Page 28
-40



Note:
The number values indicated in display fields 1 and 2 represent actual ignition angle retardation via knock control of the
individual cylinders. Ignition angle retardation occurs in KW (crankshaft degrees) toward retardation.
- Press -C- button.Read Measurin
g Value Block
Q
Input displa
y group number XXX

When indicated on display:
- Press buttons -0-, -2- and -2- to select "display group number 022" and press -Q-
button to confirm input.
Read Measuring Value Block 22
1
2
3
4

When indicated on display:
- Check indications in display field 3 and 4.
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Display fields

1 2 3 4
Display group 022: Ignition -knock control in driving operation
Display xxxx/min xxx.x %
xx.x KW
xx.x KW
Indicated Engine speed
(RPM) Engine
load Ignition angle retardation cylinder 1
via knock control
Knock sensor control Ignition angle retardation cylinder 2
via knock control
Knock sensor control
Specified
value xxxx/min 12 to 100
% 0 to 12 KW
0 to 12 KW
Notes Evaluation Page 28
-40

Note:
The number values indicated in display fields 3 and 4 represent actual ignition angle retardation via knock control of cylinders
1 and 2. Ignition angle retardation occurs in KW (crankshaft degrees) toward retardation.
- Press -C- button.Read Measurin
g Value Block
Q
Input displa
y group number XXX

When indicated on display:
- Press buttons -0-, -2- and -3- to select "display group number 023" and press -Q-
button to confirm input.
Read Measuring Value Block 23
1
2
3
4

When indicated on display:
- Check indications in display field 3 and 4.
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Display fields

1 2 3 4
Display group 023: Ignition -knock control in driving operation
Display xxxx/min xxx.x %
xx.x KW
xx.x KW
Indicated Engine speed
(RPM) Engine
load Ignition angle retardation cylinder 3
via knock control
Knock sensor control Ignition angle retardation cylinder 4
via knock control
Knock sensor control
Specified
value xxxx/min 12 to 100
% 0 to 12 KW
0 to 12 KW
Notes Evaluation Page 28
-40

Note:
The number values indicated in display fields 3 and 4 represent actual ignition angle retardation via knock control of cylinders
3 and 4. Ignition angle retardation occurs in KW (crankshaft degrees) toward retardation.
- Press -C- button.Read Measurin
g Value Block
Q
Input displa
y group number XXX

When indicated on display:
- Press buttons -0-, -2- and -4- to select "display group number 024" and press -Q-
button to confirm input.
Read Measuring Value Block 24
1
2
3
4

When indicated on display:
- Check indications in display field 3 and 4.
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Display fields

1 2 3 4
Display group 024: Ignition -knock control in driving operation
Display xxxx/min xxx.x %
xx.x KW
xx.x KW
Indicated Engine speed
(RPM) Engine
load Ignition angle retardation cylinder 5
via knock control
Knock sensor control Ignition angle retardation cylinder 6
via knock control
Knock sensor control
Specified
value xxxx/min 12 to 100
% 0 to 12 KW
0 to 12 KW
Notes Evaluation Page 28
-40

Note:
The number values indicated in display fields 3 and 4 represent actual ignition angle retardation via knock control of cylinders
5 and 6. Ignition angle retardation occurs in KW (crankshaft degrees) toward retardation.
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Evaluation display groups 020/021/022/023/024 - ignition angle retardation
Indicated on display
Possible cause
Corrective action
All cylinders more than 12 KW
Knock sensor faulty- Check knock sensor Page 28
-41

Harness connector corroded
Knock sensor incorrect
tightening torque - Loosen knock sensors and tighten to 20
Nm
Engine accessories loose- Secure engine accessories
Poor fuel quality- Change fuel quality
(see operating instructions)
One cylinder deviates significantly from
the others Harness connector corroded- Check knock sensor Page 28
-41

Engine damage
Repair Manual, Engine Mechanical,
Repair Group 15 - Check compression pressure:

Engine accessories loose- Secure engine accessories
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Knock sensors, checking

Special Tools and Equipment

VAG1526A
VAG1594A
VAG1598/31
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Component location Overview of Component
Locations, page Page 24
-5

Notes:

Knock Sensor (KS) 1 -G61- and Knock Sensor
(KS) 2 -G66- themselves cannot be electrically
tested.
Use only gold-plated terminals when servicing
harness connector for knock sensors.
For the knock sensors to function properly, it is
important that tightening torque be exactly 20
Nm.
Check harness connector from knock sensor to
wiring harness for corrosion.

Check knock sensors

Note:
Coolant reservoir screws must be removed and coolant reservoir must be
placed to side in order to access harness connector for knock sensor for
bank 2. The coolant hoses can remain connected. - Disconnect the harness connector of the relevant knock sensor in
engine compartment.
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Check wires from knock sensors to Engine Control Module (ECM). - Check all three terminals at knock sensor connector for short circuit to
each other (terminal 1+2, 1+3, 2+3).

Specification: (no continuity) - the wires must not have any
connection to each other.
- If there is no connection , replace knock sensor.
- If no short circuit is detected, check knock sensor wires:
- Connect VAG1598/31 test box at wiring harness to ECM, do not
connect ECM Page 24
-17
.
- Check the following wire connections for open circuit and short circuit
to Ground (GND) and B+:

Knock Sensor (KS) 1 -G61- Harness connector
Terminal
VAG1598/31 test box
Socket
1 (signal) 106
2 (Ground -GND-) 99
3 (shielding) 108
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Knock Sensor (KS) 2 -G66- Harness connector
Terminal
VAG1598/31 test box
Socket
1 (signal) 107
2 (Ground -GND-) 99
3 (shielding) 108
- Repair open circuit or short circuit if necessary.
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Camshaft Position (CMP) sensor,
checking

Special Tools and Equipment

VAG1526A
VAG1527B
VAG1594A
VAG1598/31
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