Audi Workshop Service and Repair Manuals > A4 Mk1 > Power unit | 4-cylinder engine (5-valve turbo), mechanics | Exhaust system | Secondary air system | Secondary air system

Secondary air system - exploded view of components

1 -	Secondary air pump motor -V101-

q	Fitting location → Fig.

q	Checking voltage supply → Anchor

2 -	Air cleaner

3 -	Combination valve for secondary air system

q	Fitting location → Fig.

q	Checking for correct operation and leakage → Chapter.

4 -	Non-return valve

q	Installation position: as shown in illustration, the arrow points in direction of flow

5 -	Secondary air pump relay -J299-

q	Fitting location → Fig.

q	Checking → Chapter

6 -	Motronic control unit -J220-

7 -	Vacuum reservoir

q	Fitting location: in front left wheel housing beneath liner

8 -	Secondary air inlet valve -N112-

q	Fitting location → Fig.

q	Checking → Chapter

9 -	Cylinder head

Fitting location of secondary air inlet valve -N112-

t	Below intake manifold

1 -	Turbocharger air recirculation valve -N249- (green connector)

2 -	Secondary air inlet valve -N112- (brown connector)

Note

For illustration purposes, the installation position is shown from the bottom and with the intake manifold removed.

Fitting location of secondary air pump motor -V101-

t	At front right of engine compartment, below longitudinal member.

Fitting location of secondary air pump relay -J299-

t	Located in 3-position relay carrier in electronics box in plenum chamber.

1 -	Motronic control unit -J220-

2 -	Secondary air pump relay -J299-

3 -	Motronic current supply relay -J271-

4 -	Secondary air pump fuse -S130-

Fitting location of combination valve for secondary air system

t	On rear right of cylinder head.

Note

For illustration purposes, the installation position is shown from the rear and with the engine removed.

Audi Workshop Service and Repair Manuals