wiring AUDI A4 1995 B5 / 1.G AWM Engine Tank Ventilation Checking Workshop Manual

24-117

Checking voltage supply

Test requirements:

Fuse for the EVAP valve OK.

Electrical Wiring Diagrams, Troubleshooting &
Component Locations

Fuel Pump (FP) relay OK; checking Page 24
-52
.

Note:
Voltage is supplied to the EVAP valve via the
Fuel Pump (FP) relay.

- Disconnect connector at EVAP valve.

- Connect VAG1527B voltage tester as follows:Harness connector
Terminal
Measure to
1 Engine Ground (GND)
- Operate starter briefly (engine can also start).

LED must light up.
Pa
ge 4 of 6 Tank ventilation, checkin
g
11/22/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU07.24.3

24-118
If LED does not light up:

- Check wire connection from terminal 1 of
connector to Fuel Pump (FP) relay via fuse for
open circuit:

Electrical Wiring Diagrams, Troubleshooting &
Component Locations
- Repair open circuit if necessary.
If LED lights up:

- Checking activation.

Checking activation

- Connect VAG1527B voltage tester to connector terminals 1 (B+) and 2.
- Initiate output DTM and activate Evaporative Emission (EVAP) canister
purge regulator valve -N80- Page 01
-51
.

LED must blink.
Pa
ge 5 of 6 Tank ventilation, checkin
g
11/22/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU07.24.3

24-119
If LED does not blink or if it remains constantly
lit:

- Connect VAG1598/31 test box at wiring harness
to Engine Control Module (ECM), do not connect
ECM Page 24
-19
.

If wire connection is OK: - Check the following wire connection for open circuit and short circuit to
Ground (GND) and B+: Harness connector
Terminal
VAG1598/31 test box
Socket
2 64
- Repair open circuit or short circuit if necessary.
- Replace Engine Control Module (ECM) Page 24
-22
Pa
ge 6 of 6 Tank ventilation, checkin
g
11/22/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU07.24.3