light AUDI A4 2000 B5 / 1.G APB Engine Ignition System Checking

28-9
If the specification is not obtained:

- Check wiring.

Electrical Wiring Diagrams, Troubleshooting &
Component Locations If the specification is obtained:

- Disconnect 3-pin harness connectors on power
output stages for ignition coils; component
locations overview Page 24
-5 .

- Then connect diode test lamp to 3-pin
connectors for both output stages.

If the specifications are not obtained: - Connect diode test lamp VAG1527 to following contacts on connectors
for power output stages: 3-pin harness connector
terminal
Specification
(with starter activated)
1 + Ground (GND) Diode test lamp should
2 + Ground (GND) light up
3 + Ground (GND)
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28-15
If the diode test lamp does not flash when testing
one or more of the contacts:
Check the Ground (GND) connections for the
power output stages as follows:

- Disconnect 4-pin harness connectors from
power output stages.

- Connect diode test lamp VAG1527 to battery
(B+) and terminal 2 of each of the 4-pin
connectors in turn.

The diode test lamp should light up.
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28-16

- If diode test lamp does not light up, test for open
circuit in wiring using wiring diagram.

Electrical Wiring Diagrams, Troubleshooting &
Component Locations
If the diode test lamp lights up:

- Replace power output stage.

Note:
Before installing new power output stage coat
metal side with heat paste (part no. G 052 170
A1). The heat paste is used to prevent corrosion
between the power output stage and the
fastening point, it is also used to transfer heat
from the power output stage.

CAUTION!

Part numbers are only for reference, always
check with your parts department for latest
information.
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11/22/2002 htt
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play?action=Goto&t
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pair&id=AUDI.B5.FU04.28.1