2000 AUDI A4 fuel pump

26-51

Checking power supply

Note:
The power supply for the secondary air injection
solenoid valve -N112- is via the fuel pump relay.

Test requirements:

Fuse for secondary air injection solenoid
valve OK.

Electrical Wiring Diagrams, Troubleshooting &
Component Locations binder

Fuel pump relay OK.

Repair Manual, 1.8 Liter 4
-Cyl. 5V Turbo Fuel
Injection & Ignition, Engine Code(s): AWM, Repair Group 24


- Disconnect connector from valve.

- Connect voltage tester VAG 1527 B as follows:Connector
Measure to
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26-52
If the LED does not light up:

- Check wiring from contact 1 on the connector
via the fuse to the fuel pump relay for an open
circuit:

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

- Check actuation.

Checking actuation

- Connect voltage tester VAG 1527 B to contacts 1 (positive) and 2 of
connector.
- Initiate output Diagnostic Test Mode (DTM) and activate secondary air
injection solenoid valve -N112-.

LED must flash.
Pa
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ystem
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p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.GE06.26.2

26-58

- Check for open circuit in wiring from
secondary air injection pump relay (in 3-
position relay carrier in E-box of plenum
chamber) via fuse S234 (in fuse box, position
34) to fuel pump relay.

Electrical Wiring Diagrams, Troubleshooting &
Component Locations binder
Check actuation of secondary air pump relay

- Switch ignition off.

- Remove secondary air injection pump relay.

- Connect voltage tester VAG 1527 B as follows:3-position relay carrier in E-box in plenum chamber,
position 2
contact
Measure to

6 Engine
Ground
- Initiate output Diagnostic Test Mode (DTM) and activate secondary air
injection pump relay.

LED must flash.
Pa
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ystem
11/21/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.GE06.26.2

26-59
If LED does not flash:

- Switch ignition off.

- Connect VAG 1598/31 test box to wiring
harness leading to engine control module;
engine control module should not be connected:

Repair Manual, 1.8 Liter 4
-Cyl. 5V Turbo Fuel
Injection & Ignition, Engine Code(s): AWM, Repair Group 24


If no malfunction is found: - Check for open circuit and short to positive or Ground in following
wiring connection: 3-position relay carrier in E-box in plenum
chamber, position 2
Contact
Test box VAG
1598/31


6 66
- Repair any open/short circuit as necessary.
- Replace Secondary Air Injection Pump relay -J299-.
Pa
ge 20 of 26 Secondar
y air s
ystem
11/21/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.GE06.26.2