Check Engine Light On Dash
Check Engine Light On, Sensor Descriptions

Knock Sensor

Choose the sensor below for descriptions
  1. Powertrain Control Module (PCM)
  2. Throttle Position (TP) sensor
  3. Mass Air Flow (MAF) sensor
  4. Intake Air Temperature (IAT) sensor
  5. Idle Air Control (IAC) valve
  6. Engine Coolant Temperature (ECT) sensor
  7. Heated Oxygen Sensor (HO2S)
  8. Camshaft Position (CMP) sensor
  9. Knock Sensor (KS)
  10. Vehicle Speed Sensor (VSS)
  11. Crankshaft Position (CKP) sensor
  12. Fuel Injector
  13. Coolant Temperature Sensor (CTS)
  14. Exhaust Gas Recirculation (EGR)
  15. Manifold Absolute Pressure (MAP)

Source: FreeAutoMechanic.com/car-engine-sensors.html

Knock Sensor (KS)

The knock sensor is used to detect engine detonation (spark knock). As a result, a voltage sent to the PCM will retard spark timing. The KS is a piezoelectric accelerometer with the sensor designed to resonate at approximately the same frequency as the engine knock frequency. The KS uses the resonant frequency to mechanically amplify the vibrations. This method allows relatively large signals to be achieved without electrical amplification and with small package size.

knock sensor