ESP AUDI A8 1997 D2 / 1.G AHA Engine Motronic Ignition System Workshop Manual

28-9

- Press buttons corresponding to following display
group numbers and press -Q- button to confirm
input.


022: Display group 22, for cylinders 1 and
2

023: Display group 23, for cylinders 3 and
4

024: Display group 24, for cylinders 5 and
6
Read Measuring Value Block 22 1 2 3 4

Indicated on display (1-4 display groups)
Note:
The test must be carried out during a road test because the knock sensor
system is only active with engine speed greater than 2600 RPM and
engine load greater than 3 ms.
WARNING!
A second technician is required to operate the VAG1551 scan tool
during the road test. Safety precautions page 24
-9 .
- Road test and compare display with specified values for knock sensor
system in display field 1-4.
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Ignition coils and power output stage,
checking


Notes:

The ignition coils and power output stage are
one component.
Measuring the primary resistance of the ignition
coils is not possible.
Measure secondary resistance first with ignition
wires connected to the ignition coil via the spark
plug connector of the respective cylinder (with
this method the interference resistances of the
ignition cables are also measured).
Component locations page 24
-1

Required special tools and test equipment

Multimeter US1119 (Fluke 83 or equivalent)
VW1594 connector test kit

Test conditions
No fuel injector malfunction stored in DTC
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Checking ignition coils -N-, -N128- and -N158-


- Disconnect 5-pin connector from ignition coil
assembly.

- Remove ignition wires from spark plugs.

If resistance is NOT OK: - Using multimeter and adapters from VAG1594 connector test kit,
measure resistance between both spark plug connectors of respective
ignition circuit (across coil).

Specification: approx. 18-25 k .- Remove ignition wires from ignition coils and measure resistance
between ends of respective ignition wires.

Specification: approx. 4.0-6.0 k
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If resistance values are not as specified:
If resistance values are OK: - Using multimeter and adapters from VAG1594 connector test kit,
measure resistance across both ignition wire connectors of respective
ignition coil.

Specification: 8.0-14.0 k - Replace coils.
- Check signal for power output stage page 28
-25
.
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