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Checking air mass meter G70 > < Checking needle lift sender G80

Golf Mk4

Checking injection timing control range
Checking injection timing control range
Special tools and workshop equipment required
t  Fault reader -V.A.G 1551- or vehicle system tester -V.A.G 1552- with diagnosis cable -V.A.G 1551/3-
t  Adapter cable, 121-pin -V.A.G 1598/31-
t  Hand multimeter -V.A.G 1526C- or multimeter -V.A.G 1715-
t  Auxiliary measuring set -V.A.G 1594C-
t  Current flow diagram
Test procedure
Checking the function of the injection timing control range is undertaken in function 04 (Basic settings). Using this procedure, the commencement of injection valve is pulsed so that the extreme values for advanced (early) and retarded (late) positions for the injection timing device can be read in display zone 3 of measured value block 4.
–  Connect fault reader -V.A.G 1551- or vehicle system tester -V.A.G 1552- and select engine electronics control unit with “address word” 01. The engine must be idling when doing this → Chapter
   
Indicated on display:
–  Press buttons 0 and 4 for function “Initiate basic settings” and confirm entry with Q button.
  
Rapid data transfer                 HELP
Select function XX
Indicated on display:
–  Press buttons 0, 0 and 4 for “Display group number 4” and confirm entry with Q button.
  
Basic setting                       HELP
Input display group number XXX
Indicated on display:
Specification in display zone 3: Advanced 7.0...9.0° BTDC
After approx. 10 seconds the timing device is moved to the retarded (late) position.
  
System in basic setting 4            ->
880 rpm   advanced  7.9° BTDC       66%
Indicated on display:
Specification in display zone 3: Retarded 3.0...5.0° BTDC
If the specifications are not achieved:
–  Check commencement of injection valve -N108- as follows:
–  Press → button.
–  Press buttons 0 and 6 for function “End data transfer” and confirm entry with Q button.
–  Switch off ignition.
Engine codes AGR, AHF, ALH, ASV
–  Disconnect 10-pin connector → Chapter
Engine codes AGP, AQM
–  Disconnect 10-pin connector → Chapter
Continuation for all engine codes
  
System in basic setting 4            ->
880 rpm   retarded  3.9° BTDC       74%
–  Measure resistance between connector contacts 9+10.
Specification: 12…20 Ω
If the specification is not achieved:
–  Renew commencement of injection valve -N108-.
If the specification is attained:
  A23-0027
–  Connect adapter cable, 121-pin -V.A.G 1598/31- to control unit wiring harness.
  N24-0943
–  Check lines between adapter cable, 121-pin -V.A.G 1598/31- and 10-pin connector for open circuit according to current flow diagram.
Contact 9+socket 114 Contact 10+sockets 1 and 2 Line resistance: max. 1.5 Ω
–  Also check wiring for short to one another, short to vehicle earth and short to battery positive.
Specification: ∞ Ω.
If no fault in lines is detected:
–  Renew diesel direct injection system control unit -J248- → Chapter.
  A23-0028

Checking air mass meter G70 > < Checking needle lift sender G80