wiring AUDI A4 1995 B5 / 1.G ATQ Engine Motronic Injection System Servicing User Guide

24-61

Voltage supply for Mass Air Flow (MAF)
sensor, checking

- Disconnect connector from Mass Air Flow (MAF)
sensor.

Note:
Voltage is supplied to Mass Air Flow (MAF) sensor from Fuel Pump (FP)
relay.
If specified value is not obtained:
Electrical Wiring Diagrams, Troubleshooting & Component Locations
binder - Connect multimeter for voltage measurement as follows.Harness connector
Terminal
Measure to
3 Engine Ground (GND)
- Operate starter briefly.

Specification: approx. battery voltage
- Check wire connection from terminal 3 of connector to Fuel Pump (FP)
relay via fuse for open circuit and short circuit to Ground (GND):
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24-63

Check wire connections for Mass Air Flow
(MAF) sensor

Note:
Signal wire is also checked during wire test.

- Connect VAG1598/31 test box at wiring harness
to ECM, do not connect ECM Page 24
-17
.

If wire connection is OK: - Check the following wire connections for open circuit and short circuit
to Ground (GND) and B+: Harness connector
Terminal
VAG1598/31 test box
Socket
1 53
2 27
4 29
- Repair open circuit or short circuit if necessary.
- Also check all wires for short circuit to each other.
- Replace Mass Air Flow (MAF) sensor -G70-.
Pa
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jection s
ystem, servicin
g
11/23/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU05.24.1