wiring AUDI A4 1998 B5 / 1.G APB Engine Motronic Multiport Fuel Injection System Servising Owner's Manual

24-73


Note:
Socket 3 on the connector is the Ground (GND) connection from the
engine control module.
If the specification is not attained: - Connect hand-held multimeter (voltage measurement range) between
sockets 2 and 3 of connector.
- Operate starter briefly.
Specification: approx. battery voltage
- Check wiring Page 24
-74
.

If the specification is not attained: - Connect hand-held multimeter (voltage measurement range) between
sockets 3 and 4 of connector.
- Switch ignition on.
Specification: approx. 5 V
- Check wiring Page 24
-74
.
Pa
ge 84 of 90 Motronic Multi
port Fuel In
jection
(MFI
) system, servicin
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.FU04.24.1

24-74

Checking wiring for mass air flow sensor

Note:
The wiring test includes also testing the signal
wire.

- Connect VAG1598/31 test box to wiring harness
for engine control module. Do not connect to the
engine control module itself Page 24
-20
.

- Check for open circuit and short to B+ or Ground (GND) in the following
wiring connections: Connector for MAF sensor -G70,
socket
VAG1598/31 test box,
socket
3 27
4 53
5 29
Pa
ge 85 of 90 Motronic Multi
port Fuel In
jection
(MFI
) system, servicin
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.FU04.24.1

24-75


Resistance in wiring: max. 1.5
- Repair short circuit or open circuit if
necessary.

Electrical Wiring Diagrams, Troubleshooting &
Component Locations

Specification: infinity (open circuit)
- If wiring and voltage supply are OK, replace
Mass Air Flow (MAF) sensor -G70.
Pa
ge 86 of 90 Motronic Multi
port Fuel In
jection
(MFI
) system, servicin
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.FU04.24.1