Checking activated charcoal filter solenoid valve 1 -N80 — AUDI

ACZ
Special tools and workshop equipment required

V.A.G 1526 A
V.A.G 1527 B
V.A.G 1594 A
V.A.G 1598 A
V.A.G 1598/12
VAS 5051 with VAS 5051/1 and VAS 5051/2

or

V.A.G 1551 with V.A.G 1551/1

Installation position => Installation position overview - Page
24-5

Note:

The activated charcoal filter system solenoid valve 1 is also referred to in this context as fuel tank breather valve of ACF valve.

Testing for leaks

ACF solenoid valve -N80 remains closed when deenergised.

Remove the hoses from the ACF valve.
Connect auxiliary hose to one connection of ACF valve.

Vehicles with control unit no. 4A0 907 473 up to software version D02 (self-diagnosis without final control diagnosis):

Unplug connector on ACF valve.
Connect contact 2 of the ACF valve to battery positive using an auxiliary cable from the V.A.G 1594 A
Connect contact 1 to earth.

The injector valve must actuate (click.)
...and must open (check by blowing into the auxiliary hose).

Remove the connection from contact 1.
It must not be possible to blow into the auxiliary hose.

If valve does not open and close properly:

Replace -N80 solenoid valve for activated charcoal filter.

If the injector does not click:

Checking internal resistance to ACF valve.

Vehicles with control unit no. 4A0 907 473 / A up to software version D03 (self-diagnosis with final control diagnosis):

Start final control diagnosis =>Page
01-42
and actuate activated charcoal filter solenoid valve -N80.

Final control diagnosis
⇒
Solenoid valve 1 for activated charcoal filter N80
Indicated on display:

The valve should click...
...and should open and close (check by blowing into the auxiliary hose).

If valve does not open and close properly:

Replace -N80 solenoid valve for activated charcoal filter.

If the injector does not click:

Checking internal resistance to ACF valve.

Checking internal resistance

Unplug connector on ACF valve.

Connect multimeter between contacts 1 and 2 to measure resistance.
Specification: 20 ... 28 ω

If the specification is not obtained:

Fit a new ACF valve.

Checking power supply

Note:

The ACF valve receives its power supply via the fuel pump relay.

Unplug connector on ACF valve.

Connect voltage tester V.A.G 1527 B as follows:

Connector / contact · Measure to
1 · Engine earth

Operate starter briefly.
The LED should light up.

If the LED does not light up:

Carry out the following tests (marked with dots):

Test fuse S73 (in brown holder -2- in the electronic box in the front passenger side footwell).

Check for open circuit between contact 1 on connector and fuse in fuse box .

=> "Current Flow Diagrams, Electrical Fault Finding and Fitting Locations" binder

Check fuel pump relay =>Page
24-47
.

Checking actuation

Vehicles with control unit no. 4A0 907 473 / A up to software version D03 (self-diagnosis with final control diagnosis):

Push back rubber grommets on connector for ACF valve but leave connector plugged in.

Connect voltage tester V.A.G 1527 B as follows:

Connector / contact · Measure to
2 · Engine earth

Start final control diagnosis =>Page
01-42
and actuate ACF solenoid -N80.
The LED should flash.

If the LED lamp does not flash or if it lights up continuously:

All vehicles:

With the ignition switched off, use adapter V.A.G 1598/12 to connect test box V.A.G 1598 A to connector D only of engine control unit (control unit remains disconnected) => Page
24-10
.

Check for open circuit and short to positive or earth in the following wiring connections:

Connector / contact · Test box V.A.G 1598 A / socket
2 · 12

Rectify any open/short circuit as necessary.

=> "Current Flow Diagrams, Electrical Fault Finding and Fitting Locations" binder

If no fault is found:

Replace engine control unit => Page
24-13
.