Knock Sensors, Checking

Knock sensors, checking


NOTE: Contact surfaces between knock sensor and cylinder block must be free of corrosion, dirt and grease.
For the Knock Sensors to function properly, it is important for tightening torque to be exactly 20 Nm.
Use only gold-plated terminals when servicing terminals in harness connector of knock sensors.

Recommended special tools and equipment
- V.A.G1526 multimeter or V.A.G1715 multimeter
- V.A.G1594 connector test kit
- Wiring diagram

Test requirements
- Knock sensor securing bolt tightened to 20 Nm.
- Ignition switched off.

Checking resistance






- Disconnect 2-pin connector for Knock Sensor (KS) 1 -G61- (-1-).

- Measure resistance between terminals 1 + 2, 1 + 3, and 2 + 3 on connectors to knock sensor.
Specified value: Infinite Ohms

If specified value is not obtained:
- Replace Knock Sensor (KS) 1 -G61-:

- Erase DTC memory of Engine Control Module (ECM).
- Generate readiness code.

If specified value is obtained:
- Check wires according to wiring diagram.

Checking wiring
- Connect test box to control module wiring harness.

Vehicles > 08.99






- Check wires between test box and 3-pin connector to Engine Control Module (ECM) for open circuit according to wiring diagram.
Terminal 1+socket 34
Terminal 2+socket 33
Terminal 3 + socket 56
Wire resistance: max: 1.5 Ohms

- Check wires for short circuit to each other.
Specified value: infinite ohms

Vehicles 09.99 >






- Check wires between test box and 3-pin connector to Engine Control Module (ECM) for open circuit according to wiring diagram.
Terminal 1 + socket 68
Terminal 2 + socket 67
Terminal 3 + socket 67
Wire resistance: max. 1.5 ohms

- Check wires terminal 1 + 2 and terminal 1 + 3 for short circuit to each other.
Specified value: infinite ohms

Continue for all vehicles

If no malfunctions are detected in the wires and the resistance values were OK:
- Replace Knock Sensor (KS) 1 -G61-:

- Erase DTC memory of Engine Control Module (ECM).
- Generate readiness code.