AUDI A4 1998 B5 / 1.G AFC Engine Fuel Injectors Checking Workshop Manual

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Fuel injectors, checking

CAUTION!

Fire hazard! Do not smoke, work near heaters
or open flame, or have anything in the area
that could ignite fuel.

Checking resistance

- Disconnect harness connector from fuel injector
to be checked.

Checking voltage supply
Repair Manual, 2.8 Liter V6 2V Engine Mechanical, Engine Code(s): AFC, Repair Group 20
- Measure fuel injector resistance using multimeter (Fluke 83 or
equivalent).
Specified value:

Bosch: 15.0 to 17.0

Siemens: 13.5 to 14.5
- Replace any fuel injector for which resistance measurement does not
fall within specified value.
Fuel pump relay OK page 24
-24

Fuel pump OK:
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Fuse for fuel injectors OK
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- Disconnect harness connector from fuel injector
to be checked.

If voltage tester does not light up:
If voltage tester does light up:
Checking fuel injector triggering - Connect VAG 1527B voltage tester between harness connector
terminal 1 and Ground (GND).
- Use scan tool "Output Diagnostic Test Mode" function 03 to trigger fuel
pump relay -J17- Repair Group 01. Specified value: voltage tester must light up
- Check wiring between terminal 1 and fuel injector fuse using wiring
diagram.
- Check fuel injector triggering.
- Disconnect harness connector from fuel injector to be checked.

- Connect VAG 1527B voltage tester between terminal 2 and battery
positive voltage (B+) using jumper wires from connector test kit VW
1594.
- Operate starter for several seconds (OK for engine to turn).
Voltage tester must flash
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If tester does not flash, check wiring between
terminal 2 of the respective fuel injector and the
ECM as follows:

- Connect VAG 1598/19 test box to ECM harness connector Repair
Group 01. - Check fuel injector 1 signal wire for continuity between harness
connector terminal 2 and test box socket D1.

Specified value: max. 1 - Check fuel injector 2 signal wire for continuity between harness
connector terminal 2 and test box socket D2.

Specified value: max. 1 - Check fuel injector 3 signal wire for continuity between harness
connector terminal 2 and test box socket D4.

Specified value: max. 1 - Check fuel injector 4 signal wire for continuity between harness
connector terminal 2 and test box socket D5.

Specified value: max. 1 - Check fuel injector 5 signal wire for continuity between harness
connector terminal 2 and test box socket D6.

Specified value: max. 1
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- Check fuel injector 6 signal wire for continuity
between harness connector terminal 2 and test
box socket D8.


Specified value: max. 1 If continuity is not obtained:

If voltage tester does not flash for each fuel injector:
If the voltage supply is OK: - Eliminate open or short circuit between terminal 2 of respective fuel
injector connector, and ECM connector. Cylinder number (fuel injector terminal 1)
Connector D terminal
1 1
2 2
3 4
4 5
5 6
6 8 - Check voltage supply for ECM page 28
-27
.
- Replace ECM Repair Group 01.
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