volkswagen Workshop Repair Guides

Volkswagen Workshop Service and Repair Manuals

ABOUT US
Checking air mass meter G70 > < Check 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 -V.A.G 1598/22-
t  Hand multimeter -V.A.G 1526C- or multimeter -V.A.G 1715-
t  Adapter set -V.A.G 1594C-
t  Current flow diagram
Test procedure
The injection timing control range check is carried out in function 04 (Basic settings). Using this procedure, the commencement of injection valve -N108- is pulsed so that the extreme values for advanced (early) and retarded (late) positions for the timing device can be read in display zone 3 of measured value block 004.
–  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 running at idle 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 keys 0, 0 and 4 for “Display group number 4” and confirm entry with Q key.
  
Basic setting                       HELP
Input display group number XXX
Indicated on display:
Specification in display zone 3: 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    adv.     7.9 ° BTDC      66 %
Indicated on display:
Specification in display zone 3: 3.0...5.0° BTDC
If the specifications are not reached:
–  Check commencement of injection valve as follows:
–  Press → button.
–  Press keys 0 and 6 for function “End data transfer” and confirm entry with Q key.
–  Switch off ignition.
Engine codes AGR, AHF, ALH
–  Separate 10-pin connector → Chapter.
Engine codes AGP, AQM
–  Separate 10-pin connector → Chapter.
Continuation for all engine codes
  
System in basic setting 4            ->
880 rpm    ret.     3.9 ° BTDC      74 %
–  Measure resistance between connector contacts 9+10.
Specification: 12…20 Ω
If the specification is not reached:
–  Renew commencement of injection valve -N108- → Item.
If the specification is attained:
  A23-0027
–  Connect adapter -V.A.G 1598/22- to control unit wiring harness.
  N24-0709
–  Check wiring between adapter and 10-pin connector for open circuit using current flow diagram. Contact 9+socket 79 contact 10+socket 2+28.
Cable 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 > < Check needle lift sender G80