Operation CHARM: Car repair manuals for everyone.
Manuals through 2025 now available!

Our trusted friends have launched a new website named LEMON, which has newer manuals. It also contains all the CHARM manuals.

LEMON is the logical successor to CHARM, I recommend you try it!

Link: lemon-manuals.la

Knock Sensor: Description and Operation



Knock Sensor:





Knock Sensor
The knock sensor is installed on the cylinder block, and senses knocking that occurs in the engine.

The sensor is a piezo-electric type which converts vibration resulting from knocking into electric signals.

In addition to a piezo-electric element, the sensor has a weight and case as its components. If knocking occurs in the engine, the weight in the case moves causing the piezo-electric element to generate a voltage.

The knock sensor harness is connected to the bulkhead harness.