volkswagen Workshop Repair Guides

Volkswagen Passat Workshop Service and Repair Manuals

Diesel injection and glow plug system > < Checking ignition transformer
Motronic injection and ignition system (6-Cyl. engine)
Servicing ignition
Checking knock sensors

Special tools, testers, measuring instruments and auxiliary items required

  • ◆ Test box V.A.G 1598/18
  • ◆ Hand multimeter V.A.G 1526 or multimeter V.A.G 1715
  • ◆ Diode test lamp V.A.G 1527
  • ◆ Adapter set V.A.G 1594
  • ◆ Current flow diagram
 
V29-0062

Test sequence

  • ‒ → Connect test box V.A.G 1598/18 to control unit wiring loom.
 
N28-0026

Knock sensor 1 (G61)

  • ‒ → Detach white 3 pin connector to knock sensor 1 -arrow-.
 
N28-0027

Knock sensor 2 (G66)

  • ‒ → Detach black 3 pin connector to knock sensor 2 -arrow-.
 
N28-0028
  • ‒ → Measure resistance between the contacts 1+2, 1+3 and 2+3 at connection to knock sensor.
         Specification: ∞ω
 
N29-0006
  • ‒ → Check wiring between test box and 3 pin connector for open circuit according to current flow diagram.
              G61:     G66:
         Contact 1+socket     34     57
         Contact 2+socket     33     33
         Contact 3+socket     56     56
         Wire resistance: Max. 1.5 ω
  • ‒ Additionally check wires for short to one another.
              G61:     G66:
         Contact 2+socket     34     57
         Contact 3+socket     33     33
         Contact 3+socket     34     57
         Specification: ∞ω

If no wiring fault is detected:

  • ‒ Loosen knock sensor and tighten again to 20 Nm.

If the fault is still present (fault again in fault memory):

  • ‒ Replace appropriate knock sensor (G61 and/or G66) =>Page 28-5 .

Diesel injection and glow plug system > < Checking ignition transformer