2000 AUDI A6 AHA Engine Multiport Fuel Injection And Ignition System Workshop Manual

24-101
If the wiring is OK, but the LED test light does not
light up:

- Replace Motronic ECM -J220- page 01
-68
.

- Carry out adaptation of throttle valve control
module to ECM page 24
-150
.

- Check readiness code page 01
-70
. If
Diagnostic Trouble Code (DTC) memory has
been erased, or ECM was disconnected,
generate new readiness code page 01
-73
.
If the wiring is OK, and the signal to the fuel
pump relay is OK:

- Replace fuel pump relay -J17-.

- Reinstall fuses.
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24-102

Fuel injectors, checking


WARNING!

Fire hazard! Do not smoke, work near heaters
or open flame, or have anything nearby that
could ignite fuel. The fuel system is under
pressure. Before opening, cover connections
with a rag, and open carefully to release
pressure.
Activating fuel injectors via output Diagnostic
Test Mode (DTM) page 01-51


Required special tools and test equipment

VAG1598/22 test box
Multimeter US1119 (Fluke 83 or equivalent)
VAG1527B LED voltage tester
VW1594 connector test kit
Wiring diagram

Test requirements

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Fuse for fuel injectors OK
Engine speed (RPM) sensor OK
Fuel pump relay OK
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24-103

Checking signal from ECM

- Disconnect harness connector from cylinder 1 fuel injector.
- Connect VAG1527B LED voltage tester between connector terminals
(to ECM), using adapter cables from VW1594 connector test kit.
- Disconnect harness connectors from fuel injectors for cylinders 2-6.
- Crank starter briefly to check voltage supply for cylinder 1 fuel injector.
LED must flicker.
- Repeat test for fuel injectors for cylinders 2-6.
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24-104
If LED does not flicker:

- Switch ignition off.

- Connect VAG1598/22 test box to ECM harness
connector page 01
-67
.

- Check wiring for open circuits between ECM/test
box and fuel injector harness connectors:


Cyl. 1 fuel injector terminal 2 to ECM/test
box socket 73

Cyl. 2 fuel injector terminal 2 to ECM/test
box socket 80

Cyl. 3 fuel injector terminal 2 to ECM/test
box socket 58

Cyl. 4 fuel injector terminal 2 to ECM/test
box socket 65

Cyl. 5 fuel injector terminal 2 to ECM/test
box socket 72

Cyl. 6 fuel injector terminal 2 to ECM/test
box socket 79
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Specified value: max. 1.5
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24-105

- Check wiring for open circuit between fuel
injector connector terminal 1 and relay panel,
according to wiring diagram.


Specified value: max. 15
- Check wiring for short circuits between wires
and connector terminals.


Specified value:
Fuel injector resistance, checking

If resistance is NOT OK: - Check resistance of individual fuel injectors.

Specified value: 13.5-15.5 - Replace affected fuel injector.
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24-106

Fuel injectors, checking for leakage


WARNING!

Fire hazard! Do not smoke, work near heaters
or open flame, or have anything nearby that
could ignite fuel. The fuel system is under
pressure. Before opening, cover connections
with a rag, and open carefully to release
pressure.

Required special tools and test equipment

VW1594 connector test kit
VAG1348/3A remote control connection
VAG1348/3-2 adapter cable
VAG1602 fuel analyzer

Test requirement
Fuel pressure regulator OK page 24
-111

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port Fuel In
jection
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) and i
gnition s
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11/23/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU03.24.1