Knock Sensor: Description and Operation

GF07.04-P-6030KE Component Description For The Knock Sensor
- up to model year 08

Component Identification:

The knock sensor is located at the left rear on the cylinder housing.

Component Identification:

Task
The knock sensor detects vibrations on the cylinder housing for anti-knock control.

Knock sensor signal may also indicate engine damage (e.g. increased engine noise resulting from widened piston grooves).

Component Identification:

Function
The vibrations on the cylinder housing are converted by the interior piezo-crystal on the knock sensor into electrical voltage signals. These signals are transmitted over a 2-pin screened line to the ME control unit (N3/10).

Piezo-electric effect: An electrical voltage is generated by the mechanical force on a piezo crystal.