XK-8 Convertible (X100) V8-4.0L (AJ27) (2001)
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Knock Sensor: Description and Operation
Knock Sensor
'Knocking' or 'pinking' is caused by uncontrolled combustion and can result in engine damage as well as excessive emissions. Knocking noises are
essentially vibrations with frequencies that are detected by a piezo-electric sensing element and converted into electrical signals. Two knock sensors are
strategically located on the engine casing and switched to the firing sequence so that knocking from any cylinder may be detected.
High/Low Input Failure
High and low input failure of the knock sensor is detected in the knock sensor processor and is then transmitted to the ECM. The Direct Current (DC)
voltage of the sensor is compared with the upper and lower limits in order to judge high or low input failure.
Knock Sensor Processor Failure
Knock sensor processor failure is detected within the processor and is then transmitted to the ECM.
