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Checking fuel tank breather > < Engine code: APF

Golf Mk4

Checking solenoid valve 1 for activated charcoal filter
Checking solenoid valve 1 for activated charcoal filter
Only engine code APF
When there is no electrical signal the solenoid valve remains closed.
Checking activation → Rep. Gr.01
Special tools and workshop equipment required
t  Fault reader -V.A.G 1551-
  Note
The vehicle system tester -V.A.G 1552- can be used instead of the fault reader -V.A.G 1551-, however a print-out is not possible.
Functional check
l  Coolant temperature must be at least 80 °C, ⇒ display group 04, display zone 3.
   
l  Fuse 43 must be OK.
–  Connect fault reader -V.A.G 1551- (vehicle system tester -V.A.G 1552-). Start engine and select “Address word” 01 of engine control unit. Connect fault reader and select engine control unit → Rep. Gr.01.
  N24-0588
Indicated on display:
–  Press keys 0 and 4 for function “Imitate basic settings” and confirm entry with Q key.
  
Rapid data transfer                 HELP
Select function XX
Indicated on display:
–  Press keys 0, 7 and 0 for “Display group number 70” and confirm entry with Q key.
  Note
No engine loading may be created during this diagnosis, otherwise the test will be terminated and can only be reinitiated by a bust of the throttle.
  
Basic setting                           
Input display group number XXX
Indicated on display: (1...4 = display zones)
When the diagnosis of the engine control unit has been initiated the display in display zone 4 will jump from “Test OFF” to “Test ON”.
–  Allow engine to continue to run at idling speed until the result of the brief test is displayed in display zone 4: Specification “TBV OK”.
  Note
t  TBV means: Tank breather valve (activated charcoal filter system solenoid valve 1).
t  When the display jumps from “Test ON” to “Test OFF” during the test, give a brief burst on the throttle and the test will be repeated.
If display zone 4 displays “TBV n.OK”:
–  Start final control diagnosis and select activated charcoal filter solenoid valve 1 -N80-: → Rep. Gr.01.
If the specification “TBV OK” is attained:
–  Press the → key.
  
System in basic setting 70            ->
        1       2       3       4
Indicated on display:
–  Press keys 0 and 6 for function “End data transfer” and confirm entry with Q key.
–  Switch off ignition.
  
Rapid data transfer                 HELP
Select function XX

Checking fuel tank breather > < Engine code: APF