ECO mode AUDI A3 1998 8L / 1.G AEB ATW Engines Secondary Air System Workshop Manual

26-34

Test requirement

Output Diagnostic Test Mode (DTM)
performed

Checking internal resistance

- Disconnect green harness connector from
Secondary Air Injection (AIR) solenoid valve -
N112-.

- Connect multimeter at valve for resistance measurement.

Specified value: 25-35
- If specified value is not obtained, replace Secondary Air Injection (AIR)
solenoid valve -N112-.
Pa
ge 6 of 16 Secondar
y air s
ystem, checkin
g (en
gine code ATW
)
11/18/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.GE02.26.2

26-36


Electrical Wiring Diagrams, Troubleshooting & Component Locations
Repair Manual, Fuel Supply System, Repair Group 20

Checking activation
Check wire connection from terminal 1 of connector via fuse S234 (in
fuse holder, socket 34) to Fuel Pump (FP) relay for open circuit: Check Fuel Pump (FP) relay

- Connect VAG1527B voltage tester between terminals 1 and 2 using
test leads from VAG1594A.
- Connect VAG1551 scan tool.
- Initiate output Diagnostic Test Mode (DTM) and activate Secondary Air
Injection (AIR) solenoid valve -N112-.
Output Diagnostic Test Mode Secondary Air Inj. Solenoid Valve -N112

Indicated on display

LED must blink.
Pa
ge 8 of 16 Secondar
y air s
ystem, checkin
g (en
gine code ATW
)
11/18/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.GE02.26.2

26-39
Installation location:

Repair Manual, 1.8 Liter 4-Cyl. 5V Turbo Fuel
Injection & Ignition, Repair Group 24
- Initiate output Diagnostic Test Mode (DTM) and
activate Secondary Air Injection (AIR) pump
relay -J299-.

A - If relay does not trigger:
B - If relay triggers, but Secondary Air Injection (AIR) pump does not run:
The Secondary Air Injection (AIR) pump relay (in 3-socket relay
carrier in the E-box, at left in plenum chamber, position 2) must
trigger and the Secondary Air Injection (AIR) pump motor -V101-
must run in intervals
- Check voltage supply of Secondary Air Injection (AIR) relay Page
26
-40
.
- Checking activation of Secondary Air Injection (AIR) relay Page 26
-
42
.
- Check voltage supply for Secondary Air Injection (AIR) pump Page
26
-43
.
Pa
ge 11 of 16 Secondar
y air s
ystem, checkin
g (en
gine code ATW
)
11/18/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.GE02.26.2

26-42

Checking activation of the Secondary Air
Injection (AIR) pump relay

- Switch ignition off.

- Remove Secondary Air Injection (AIR) pump
relay.

If LED does not blink: - Connect VAG1527B voltage tester as follows:3-socket relay carrier in E-box, plenum
chamber, position 2
terminal
Measure to

6 Engine Ground
(GND)
- Initiate output Diagnostic Test Mode (DTM) and activate Secondary Air
Injection (AIR) pump relay -J299-.

LED must blink.
- Switch ignition off.
- Connect VAG1598/31 test box at wiring harness to ECM, do not
connect ECM.
Pa
ge 14 of 16 Secondar
y air s
ystem, checkin
g (en
gine code ATW
)
11/18/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.GE02.26.2

26-43


If no malfunctions are detected:
Checking voltage supply of the Secondary Air Injection (AIR) pump
motor - Check the following wire connection for open circuit and short circuit to
Ground (GND) and B+: 3-socket relay carrier in E-box, plenum
chamber, position 2
terminal
VAG1598/31 test
box
socket
6 46
- Repair open circuit or short circuit if necessary.
- Replace Secondary Air Injection (AIR) pump relay -J299-.
- Remove harness connector for Secondary Air Injection (AIR) pump
motor -V101-.
- Connect VAG1527B voltage tester between terminals 1 and 2.
- Initiate output Diagnostic Test Mode (DTM) and activate Secondary Air
Injection (AIR) pump relay -J299- Page 26
-42
.

LED must light.
Pa
ge 15 of 16 Secondar
y air s
ystem, checkin
g (en
gine code ATW
)
11/18/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.GE02.26.2