Checking turbocharger air recirculation vale N249 - engine codes ANB, APU, ARK, ATW — AUDI

Checking
turbocharger air recirculation vale
N249
- engine codes ANB, APU, ARK, ATW
Special tools and workshop equipment required
Hand-held multimeter
V.A.G 1526D
Voltage tester
V.A.G 1527B
Auxiliary measuring set
V.A.G 1594C
Adapter cable, 121-pin
V.A.G 1598/31
Vehicle diagnostic, testing and information system
VAS 5051B
Procedure
Note
Air recirculation valve for turbocharger
N249
and its wiring are monitored by the engine control unit.
Vehicle diagnostic, testing and information system
VAS 5051B
connected.
Engine running.
Vehicle self-diagnosis
and vehicle system
“01 - Engine electronics”
selected.
Display on
VAS 5051B
:
From menu
1
, select diagnostic function
“Interrogate fault memory”
and press
→
key to continue.
If the display shows a fault relating to
air recirculation valve for turbocharger
N249
:
Press
←
key to exit function
“Interrogate fault memory”
.
Select
“End output”
.
Switch off ignition.
Disconnect hoses from
turbocharger air recirculation valve
N249
item 1
; leave electrical connector attached.
Fitting location: below intake manifold
Note
The illustration shows the intake manifold from below and removed from the engine.
Connect a test hose to the hose connection on the
turbocharger air recirculation valve
N249
marked with an
arrow
.
Switch on ignition and select vehicle system
“01 - Engine electronics”
again.
Display on
VAS 5051B
:
From menu
1
select diagnostic function
“Final control diagnosis”
.
Press the
→
key repeatedly until the following display appears:
Display on
VAS 5051B
:
6
Turbocharger air recirculation valve
N249
A
Actuator is running; continued switching is allowed
The valve will be activated intermittently for approx. 1 minute (and should click audibly).
The valve should open and close (check by blowing into the test hose).
Press
←
key to exit diagnostic function
“Final control diagnosis”
.
Select function
“End output”
and switch off ignition.
If valve clicks but does not open or close correctly:
Renew
air recirculation valve for turbocharger
N249
.
If valve does not click:
Checking internal resistance
Unplug electrical connector at
turbocharger air recirculation valve
N249
item 1
.
Connect
hand-held multimeter
V.A.G 1526D
to valve (resistance measurement range).
Specification: 27 ... 30 Ω.
If reading does not match specification, renew
turbocharger air recirculation valve
N249
.
If the specification is attained:
Checking voltage supply
Fuse for
turbocharger air recirculation valve
N249
OK
Current flow diagrams, Electrical fault finding and Fitting locations
.
Fuel pump relay
J17
OK
Rep. gr.
24
.
Note
Turbocharger air recirculation valve
N249
is supplied with power via
fuel pump relay
J17
.
Connect
voltage tester
V.A.G 1527B
between contact
1
of connector for
turbocharger air recirculation valve
N249
and earth
“–”
.
Briefly operate starter.
The LED should light up.
If LED does not light up, check for open circuit in wiring from contact
1
of connector for
turbocharger air recirculation valve
N249
via fuse to
fuel pump relay
J17
Current flow diagrams, Electrical fault finding and Fitting locations
.
Repair wiring connection if necessary.
If the LED lights up:
Checking activation
Connect
voltage tester
V.A.G 1527B
between contact
1
and
2
of connector for
turbocharger air recirculation valve
N249
.
Switch on ignition and select vehicle system
“01 - Engine electronics”
.
Repeat diagnostic function
“Final control diagnosis”
.
Press the
→
key repeatedly until the following display appears:
Display on
VAS 5051B
:
6
Turbocharger air recirculation valve
N249
A
Actuator is running; continued switching is allowed
The LED should flash.
Press
←
key to exit diagnostic function
“Final control diagnosis”
.
Select
“End output”
.
Switch off ignition and unplug diagnostic connector.
If LED does not flash or lights up continuously, connect
adapter cable, 121-pin
V.A.G 1598/31
(test box) to connectors of wiring harness; do not connect engine control unit. Connect earth clip of test box to earth
Rep. gr.
24
.
Caution
Electronic components are susceptible to damage.
Select the appropriate measuring range before connecting the test leads and observe test requirements.
Check for open circuit and short to positive or earth in the following wiring for
turbocharger air recirculation valve
N249
.
Connector
Contact
V.A.G 1598/31
Socket
2
105
Repair wiring connection if necessary.