Volkswagen Workshop Service and Repair Manuals

Check for Digifant 3.2 only (10.94▸)

(Interrogate control unit version ; Connecting fault reader V.A.G 1551 and selecting engine electronics control unit).

Special tools, testers and auxiliary items

• ◆ Fault reader V.A.G 1551 or vehicle system tester V.A.G 1552 with cable V.A.G 1551/3

Check conditions

• ● Idling adjustment OK.
• ● Coolant temperature at least 85 °C

Test sequence

Functional check

• ‒ Functional check , final control diagnosis.

Checking regulation

• ‒ Connect fault reader V.A.G 1551 (V.A.G 1552) and select engine electronics control unit with the "Address word" 01. When doing this the engine must be running at idling speed.
  (Connecting fault reader and selecting engine electronics control unit => Page 01-4 .)

• ‒ Input 08 for "Read measured value block" function and confirm with Q key.

• ‒ Enter 03 for "Display group number" and confirm with Q key.

• ‒ Allow engine to idle for at least 1 minute.
• ‒ Read off figure displayed in display zone 4.
       Specification: 7...25 %
  (Idling speed 770...890 rpm)
• ‒ Press ⇒key.
• ‒ Input 06 for "End output" and confirm with Q key.

If the specification is exceeded:

• ‒ Check air intake system for leaks
  => Page 24-82 .
• ‒ Renew idling speed stabilization valve
  => Page 24-14 , item 11 .
• ‒ Renew Digifant control unit (J169)
  , item 11 .