AUDI A4 1997 B5 / 1.G APB Engine Charge Air System With Turbocharger Owner's Guide

21-26
If wire connection is OK:

- Replace Engine Control Module (ECM).

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

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21-27


Charge air pressure sensor -G31-,
checking

Special tools and equipment

VAG 1526A
VAG 1594A
VAG 598/31
VAS 5051 with VAG 5051/1
- or
VAG 1551 with VAG 1551/3A
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21-28

Note:
The charge air pressure sensor -G31- and wire
connections are monitored by the Engine Control
Module (ECM).

- Connect VAS 5051 tester or VAG 1551 scan
tool and select control module for engine
electronics using "address word" 01. Engine
must run at idle.

Repair Manual, 2.7 Liter V6 5V BiTurbo Fuel
Injection & Ignition, Engine Code(s): APB, Repair Group 01


- Check DTC memory of Engine Control Module
(ECM).

Repair Manual, 2.7 Liter V6 5V BiTurbo Fuel
Injection & Ignition, Engine Code(s): APB, Repair Group 01

If a Diagnostic Trouble Code (DTC) relating to
the charge air pressure sensor -G31- is
indicated:
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21-29

Checking voltage supply

- Switch ignition off.

- Remove engine cover (arrows).
- Disconnect connector at charge air pressure sensor.

If specified value is not obtained: - Connect multimeter between terminal 1 and 3 of harness connector for
voltage measurement.
- Switch ignition on.

Specification: about 5 V
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21-30

- Connect VAG 1598/31 test box to wiring
harness for Engine Control Module (ECM), also
connect ECM -1-.

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


If the specified value is met: - Check the following wire connections for open circuit and short circuit
to Ground (GND) and B+: Harness connector terminal
VAG 1598/31 or test box
Bushing
1 108
3 98
- Repair open circuit or short circuit if necessary.
- Check signal wire, Page 21
-31
.
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21-31

Checking signal wire

- Disconnect harness connector at charge air
pressure sensor.

- Connect multimeter to socket 101 and socket
108 of test box for voltage measurement.

- Start engine and run at idle.


Specification: about 1.90 V

- Bring engine to RPM by depressing pedal
suddenly.

Specification: approx. 2.00 ... 3.00 V
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21-32
If specified values are not obtained:

If wire connection is OK: - Check following wire connection for open circuit and short circuit to
Ground (GND) and B+: Harness connector terminal
VAG 1598/31 or test box
Bushing
4 101
- Repair open circuit or short circuit if necessary.
- Replace charge air pressure sensor -G31-.
Pa
ge 37 of 37 Char
ge air s
ystem with turbochar
ger
11/21/2002 htt
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play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.GE05.21.1