check engine light AUDI A4 1995 B5 / 1.G APB Engine Exhaust System Components Workshop Manual

26-25

Checking voltage supply

- Switch ignition off.

- Remove engine cover (arrows).
- Disconnect connector at exhaust gas temperature sensor.

- Connect VAG 1527B voltage tester as follows:Harness connector terminal
Measure to
3 Engine Ground (GND)
- Operate starter briefly.

LED must light.
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26-26
If LED does not light:

- Perform following tests marked with dots:

Electrical Wiring Diagrams, Troubleshooting & Component Locations
Repair Manual, 2.7 Liter V6 5V BiTurbo Fuel Injection & Ignition,
Engine Code(s): APB, Repair Group 24

Repair Manual, 2.7 Liter V6 5V BiTurbo Fuel Injection & Ignition,
Engine Code(s): APB, Repair Group 24

Check fuse -S234- (in fuse holder, position 34). Check wire connection from exhaust gas temperature sensor via fuse
-S234- (in fuse holder, socket 34) to Fuel Pump (FP) relay for open
circuit: Check Fuel Pump (FP) relay.
- Connect VAG 1598/31 test box at wiring harness to ECM. Do not
connect ECM.
Pa
ge 26 of 30 Exhaust s
ystem com
ponents, removin
g and installin
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11/21/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
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e=re
pair&id=AUDI.B5.GE05.26.1