checking oil AUDI A6 1999 C5 / 2.G AEB Engine Ignition Coil System Checking

28-17


Individual ignition coil system,
checking

Ignition coils, checking


Notes:

Measuring the primary resistance of the ignition
coils is normally not necessary for this test
(primary resistance approx. 0.4 to 0.6 ,
measured between coil terminals 1 and 15).

A high tension isolation diode is installed in the
secondary circuit of the ignition coil. Measuring
the resistance of the secondary coil is therefore
not possible with conventional measuring
instruments.

Required special tools and test equipment
Multimeter US 1119 (Fluke 83 or equivalent)
VW 1594 connector test kit

Test conditions
No fuel injector malfunction stored in DTC
memory
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Checking

- Check DTC memory Page 01
-15
.

There must be no malfunctions stored

- If DTC memory is not clear, make necessary
repairs and erase DTC memory, stop engine
and start engine again, road test, check and
erase DTC memory again.
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28-19

Wiring for primary coil and power
supply, checking


Required special tools and test equipment

VAG 1527B LED voltage tester
VW 1594 connector test kit
Wiring diagrams

Test conditions
Fuse for ignition coils OK

Checking

- Disconnect 4-pin harness connector from power
output stage.

- Switch ignition on.

Note: - Connect VAG 1527B LED voltage tester in turn between 4-pin
connector terminals 1, 2, 3 and 4, and engine ground.
LED must light up for all 4 terminals
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28-21

Power output stage for ignition coils,
checking


Required special tools and test equipment

VAG 1598/22 test box
Multimeter US 1119 (Fluke 83 or equivalent)
VAG 1527B LED voltage tester
VW 1594 connector test kit
Wiring diagrams

Note:
To check power output stage, disconnect all
connectors for fuel injectors and then erase DTC
memory.
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28-22

Checking signal for power output stage

- Disconnect 5-pin harness connector from power
output stage.

If the LED in the tester does not blink: - Connect VAG 1527B LED voltage tester in turn between 5-pin
connector terminals 1, 2, 4 and 5, and engine ground.
- Crank starter for a few seconds in each case.
LED must blink all 4 times
- Connect VAG 1598/22 test box to ECM harness connector Page 01
-
56
.

- Check wiring for open circuit between ECM/test box and 5-pin harness
connector, according to wiring diagram.

Connector terminal 1 to ECM/test box socket 70
Connector terminal 2 to ECM/test box socket 78
Connector terminal 4 to ECM/test box socket 77
Connector terminal 5 to ECM/test box socket 71
Specified value: max. 1.5
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28-24

Checking power output stage

Signals to power output stage OK Page 28
-22
.

- Disconnect 4-pin harness connector from power
output stage.

- Connect VAG 1527B LED voltage tester
between Battery Positive Voltage (B+) and, in
turn, each terminal of power output stage 4-pin
connector.

- Crank starter for a few seconds in each case.

LED must blink all 4 times
If the LED in the tester does not blink for all
terminals:

- Replace power output stage.

Note:
LED testers with very little power consumption
glow slightly before cranking the engine. During
cranking they will get brighter or darker.
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11/19/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU02.28.2