relay AUDI A8 1996 D2 / 1.G AHA Engine Multiport Fuel Injection And Ignition System User Guide

24-99

Checking fuel pump relay voltage supply and
actuation

- Remove fuel pump relay -J17- from relay panel
position 6.

Checking fuel pump relay voltage supply

- Switch ignition on.

If voltage is NOT OK: - Connect multimeter US1119 (Fluke 83 or similar) and check for voltage
at relay socket:

Terminals 28 (B+) and 34
Terminals 32 (B+) and 34
Specified values: approx. Battery Positive Voltage (B+)
- Repair wiring according to applicable wiring diagram.
Pa
ge 127 of 166 Motronic Multi
port Fuel In
jection
(MFI
) and i
gnition s
ystem
11/23/2002 htt
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yp
e=re
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24-100

Checking fuel pump relay actuation

Note:
The LED light will light dimly before and after cranking the starter.
If the LED test light does not light up while cranking the starter, check
wiring as follows. - Connect VAG1527B LED voltage tester between relay socket terminals
28 (B+) and 29.
- Briefly crank starter.
LED test light must light up.

If resistance is NOT OK:
Electrical Wiring Diagrams, Troubleshooting & Component Locations
binder. - Connect VAG1598/22 test box to ECM harness connector page 01
-
67
. (Numbers marked on ECM connector match those on test box).
- Connect multimeter US1119 (Fluke 83 or equivalent) to check for open
circuit between relay socket terminal 29 and test box socket 4.

Specified value: max. 1 - Repair wiring using applicable wiring diagram.
Pa
ge 128 of 166 Motronic Multi
port Fuel In
jection
(MFI
) and i
gnition s
ystem
11/23/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
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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.
Pa
ge 129 of 166 Motronic Multi
port Fuel In
jection
(MFI
) and i
gnition s
ystem
11/23/2002 htt
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Fuse for fuel injectors OK
Engine speed (RPM) sensor OK
Fuel pump relay OK
Pa
ge 131 of 166 Motronic Multi
port Fuel In
jection
(MFI
) and i
gnition s
ystem
11/23/2002 htt
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play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU03.24.1

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.
Pa
ge 135 of 166 Motronic Multi
port Fuel In
jection
(MFI
) and i
gnition s
ystem
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

24-121

Checking EVAP canister purge regulator
valve voltage supply

Test conditions

Fuse for EVAP canister purge regulator
valve OK

- Disconnect harness connector from EVAP
canister purge regulator valve.

If LED test light does not light:
If wiring is OK: - Connect VAG1527B LED voltage tester between connector terminal 1
(B+) and engine Ground.
- Operate starter motor.
Specified value: LED must light up
- Check wiring for open circuit between connector terminal 1 and fuse,
according to wiring diagram; repair if necessary.

Specified value: 1.0 max.- Check fuel pump relay page 24
-95
.
Pa
ge 158 of 166 Motronic Multi
port Fuel In
jection
(MFI
) and i
gnition s
ystem
11/23/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
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24-125

Voltage supply, checking

If LED tester does not light: - Disconnect harness connector for LDP -V144-.
- Connect VAG1527B LED voltage tester between connector terminal 3
(B+) and engine Ground.
- Start engine and run engine at idle.
LED must light up.
- Check fuse for LDP -V144-.
- Check wiring for open circuit between terminal 3 and fuse, according to
wiring diagram.

Specified value: max. 0.5 .- Check fuel pump relay and signal to relay page 24
-95
.
Pa
ge 162 of 166 Motronic Multi
port Fuel In
jection
(MFI
) and i
gnition s
ystem
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