2000 AUDI A8 AEB Engine Ignition Coil System Checking

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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28-23
If the wiring is OK:

If the wiring is OK, but the LED in the tester did not blink: - Check for open circuit between 5-pin connector terminal 3 and engine
Ground.

Specified value: max. 1.5 - Replace Motronic ECM -J220- Page 01
-57
.
- Carry out adaptation of throttle valve control module to ECM Page
24
-119
.
- Check readiness code Page 01
-59
. If Diagnostic Trouble Code
(DTC) memory has been erased, or ECM was disconnected, generate
new readiness code Page 01
-62
.
Pa
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11/19/2002 htt
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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.
Pa
ge 11 of 11 Individual i
gnition coil s
ystem, checkin
g
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