1997 AUDI A4 check engine light

21-32
If the LED lamp does not flash or if it lights up
continuously:

- Connect VAG 1598/31 test box to wiring
harness leading to engine control module;
engine control module should not be connected:

Repair Manual, 1.8 Liter 4
-Cyl. 5V Turbo Fuel
Injection & Ignition, Engine Code(s): AWM, Repair Group 24


If the wiring is OK: - Check for open circuit and short to positive or Ground in following
wiring connection: Connector
Contact
Test box VAG 1598/31
2 105
- Repair any open/short circuit as necessary.
- Replace engine control module.
Pa
ge 22 of 34 Char
ge pressure leak test with VAG 1687
11/21/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.GE06.21.2

21-36

Checking power supply

Test requirements:

Fuse for wastegate bypass regulator valve
OK

Electrical Wiring Diagrams, Troubleshooting &
Component Locations binder

Fuel pump relay OK.

Repair Manual, 1.8 Liter 4
-Cyl. 5V Turbo Fuel
Injection & Ignition, Engine Code(s): AWM, Repair Group 24


- Connect voltage tester VAG 1527 B as follows:Connector
contact
Measure to
1 Engine Ground
- Operate starter briefly.

LED must light up.
Pa
ge 26 of 34 Char
ge pressure leak test with VAG 1687
11/21/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.GE06.21.2

21-38
If the LED lamp does not flash or if it lights up
continuously:

- Connect VAG 1598/31 test box to wiring
harness leading to engine control module;
engine control module should not be connected:

Repair Manual, 1.8 Liter 4
-Cyl. 5V Turbo Fuel
Injection & Ignition, Engine Code(s): AWM, Repair Group 24


If the wiring is OK: - Check for open circuit and short to positive or Ground in following
wiring connection: Connector
Contact
Test box VAG 1598/31
2 104
- Repair any open/short circuit as necessary.
- Replace engine control module.
Pa
ge 29 of 34 Char
ge pressure leak test with VAG 1687
11/21/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.GE06.21.2