1996 AUDI A4 fuel

21-49

Note:
The recirculating valve for turbocharger -N249-
and wire connections are monitored by the
Engine Control Module (ECM).

- Connect VAS5051 tester or VAG1551 scan tool
and select control module for engine electronics
using "address word 01". Engine must run at idle
for this:

Repair Manual, 1.8 Liter 4-Cyl. 5V Turbo Fuel
Injection & Ignition, Repair Group 01 If a malfunction relating to the recirculating valve
for turbocharger -N249- is displayed:

- Disconnect hoses from valve; harness connector
remains connected.

- Attach assisting hose to one connection of
valve.
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21-50

- Initiate output Diagnostic Test Mode (DTM) and
activate the recirculating valve for turbocharger -
N249-:

Repair Manual, 1.8 Liter 4-Cyl. 5V Turbo Fuel
Injection & Ignition, Repair Group 01 Output Diagnostic Test Mode Recirc. valve for turbochar
ger -N249

Indicated on display
If valve does not click:
If valve does not open and close properly:
Checking internal resistance Valve must click...
...and must open and close (can be tested by blowing into assisting
hose).
- Check internal resistance of valve.
- Replace recirculating valve for turbocharger -N249-.
- Disconnect harness connector at valve.

- Connect multimeter at valve for resistance measurement.

Specified value: 27-30
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21-51
If the specified value is attained:

- Check voltage supply

Checking voltage supply

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

Test requirement

Fuse for recirculation valve OK

- Disconnect harness connector at valve.

- Connect VAG1527B voltage tester as follows:Harness connector
terminal
Measure to
1 Engine Ground (GND)
- Operate starter briefly.

LED must light.
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21-52
If LED does not light:

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

Electrical Wiring Diagrams, Troubleshooting &
Component Locations
- Repair open circuit if necessary.
If wire connection is OK:

- Check Fuel Pump (FP) relay:

Repair Manual, 1.8 Liter 4-Cyl. 5V Turbo Fuel
Injection & Ignition, Repair Group 24 If LED lights:

- Check activation:

Checking activation

- Connect VAG1527B voltage tester to connector terminals 1 (B+) and 2.
-
Initiate output Diagnostic Test Mode (DTM) and activate the
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)
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p://127.0.0.1:8080/audi/servlet/Dis
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pair&id=AUDI.B5.GE02.21.3

Repair Manual, 1.8 Liter 4-Cyl. 5V Turbo Fuel Injection & Ignition,
Repair Group 01 recirculating valve for turbocharger -N249-:
LED must blink.
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)
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21-53
If LED does not blink or if it remains constantly
lit:

- Connect VAG1598/31 test box at wiring harness
to ECM, do not connect ECM:

Repair Manual, 1.8 Liter 4-Cyl. 5V Turbo Fuel
Injection & Ignition, Repair Group 24

If wire connection is OK:
Repair Manual, 1.8 Liter 4-Cyl. 5V Turbo Fuel Injection & Ignition,
Repair Group 24 - Check the following wire connection for open circuit and short circuit to
Ground (GND) and B+: Harness connector
terminal
VAG1598/31 test box
socket
2 105
- Repair open circuit or short circuit if necessary.
- Replace Engine Control Module (ECM):
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21-55

Test requirements

All hoses and wires have been checked for
proper seating and seal.
DTC memory checked

Repair Manual, 1.8 Liter 4-Cyl. 5V Turbo Fuel
Injection & Ignition, Repair Group 01

Output Diagnostic Test Mode (DTM)
performed

Repair Manual, 1.8 Liter 4-Cyl. 5V Turbo Fuel
Injection & Ignition, Repair Group 01

Vehicle tester VAS 5051 or VAG 1551
connected.

Test sequence

WARNING!

To reduce the risk of accident or injury while
carrying out tests and measurements during
a road test, observe safety precautions
Page 21
-40
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Pa
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ger
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gine code ATW
)
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pair&id=AUDI.B5.GE02.21.3

- Using T-piece connect test hose from VAG1397A Turbocharger Tester
between intake manifold and fuel pressure regulator.
- Guide test hose over rear corner of hood, through passenger side
window and into vehicle interior.
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ge air s
ystem with turbochar
ger
(en
gine code ATW
)
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p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.GE02.21.3