light AUDI A6 1995 C5 / 2.G AEB ATW Engines Secondary Air System Workshop Manual

26-31



To prevent unnecessary heating, the secondary
air is diverted past the turbocharger -7-. For
this, the charge air pressureregulation pressure
unit opens the charge air pressure valve. The
pressure unit, designed as a double reservoir,
has a vacuum connection for this on the intake
side.
1 -
Secondary Air Injection (AIR) pump relay -
J299-
2 -
Motronic Engine Control Module (ECM) -
J220-
3 -
Secondary Air Injection (AIR) solenoid
valve -N112-
4 -
Intake manifold
5 -
Check valve
Installation position (light/dark side): Arrow
points in direction of flow, as shown
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26-35

Checking voltage supply

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

If LED does not light: - Connect VAG1527B voltage tester as follows:Harness connector
terminal
Measure to
1 Engine Ground (GND)
- Operate starter briefly.

LED must light.
- Perform the following tests marked with dots:

Check fuse S234 (in fuse holder, position 34).
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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.
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26-44
If LED does not light:

- Perform the following tests marked with dots:

Check wire connection from harness
connector at Secondary Air Injection (AIR)
pump motor -V101- to Secondary Air
Injection (AIR) pump relay -J299- (in 3-
socket relay carrier in E-Box, plenum
chamber, position 2) for open circuit.

Electrical Wiring Diagrams, Troubleshooting &
Component Locations

Check wire connection from harness
connector at Secondary Air Injection (AIR)
pump motor -V101- to Ground (GND)
connection 1 in engine compartment wiring
harness for open circuit:

Electrical Wiring Diagrams, Troubleshooting &
Component Locations
If no malfunctions are detected:

- Replace Secondary Air Injection (AIR) pump
motor -V101-.
Pa
ge 16 of 16 Secondar
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ystem, checkin
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)
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