Component Testing
The engine knock sensor is affected by a number of factors. A few of these are:- ignition timing
- cylinder pressure
- fuel octane, etc.
The knock sensor generates an AC voltage whose amplitude increases with the increase of engine knock.
The knock sensor can be tested with a digital voltmeter:
- The RMS voltage starts at about 20mVac (at about 700 rpm) and increases to approximately 600 Vac (5,000 rpm).
- If the output falls outside of this range a DTC will be set.