Audi Workshop Service and Repair Manuals

Fitting locations overview:

Notes:

• ◆ It is extremely important to keep to the tightening torque of 20 Nm to ensure the knock sensors perform perfectly.
• ◆ Only gold-plated contacts may be used when servicing the knock sensor connector contacts.

Special tools, workshop equipment, testers, measuring instruments and auxiliary items required

• ◆ Test box V.A.G 1598/31
• ◆ Hand multimeter V.A.G 1526 or multimeter V.A.G 1715
• ◆ Adapter set V.A.G 1594
• ◆ Current flow diagram

Test conditions

• ● Knock sensor fault recognised by self-diagnosis , interrogating and erasing fault memory.

Test sequence

• ‒ → Pull 2 pin connector off knock sensor -arrow-.

• ‒ → Connect test box V.A.G 1598/31 to control unit wiring harness. The engine control unit remains disconnected .

• ‒ → Check wiring for open circuit between test box and 2-pin connector using current flow diagram.
      Contact 1+socket 106
      Contact 2+socket 99
      Wire resistance: Max. 1.5 ω
• ‒ Additionally check wires for short to one another.
      Specification: ∞ω

If no fault is detected in the wiring:

• ‒ Loosen knock sensor and tighten again to 20 Nm.
• ‒ Carry out test drive.

Observe the valid safety precautions when carrying out a test drive => Page 28-6.

• During the road test the following operating conditions must be fulfilled:
• ‒ The coolant temperature must exceed 80 °C .

• ‒ When the temperature is reached, the operating conditions
      Idling
      Part throttle
      Full throttle
      Overrun
  must be attained several times.
• ‒ At full throttle the speed must exceed 3500 rpm.
• Again interrogate the control unit fault memory.

If the fault is still present:

• ‒ Replace knock sensor (G61) , item 6.