What does it mean when the knock sensor of the 7th generation Accord has no signal?

[DiEloise]

This indicates that the sensor is malfunctioning or the wiring is not properly connected. The function of the knock sensor is to transmit engine knock in the form of an electrical signal to the electronic control module, serving as a crucial basis for the control module to adjust ignition timing to prevent further knocking. Below is relevant information: Function: The knock sensor is installed in the middle of the engine block. For a four-cylinder engine, it is placed between cylinders 2 and 3, or one between cylinders 1 and 2 and another between cylinders 3 and 4, to measure engine vibration and adjust the ignition advance angle when engine knock occurs. Types: There are various types of knock sensors, with the earliest being the magnetostrictive knock sensor, which mainly consists of a magnetic core, permanent magnet, and induction coil. When the engine vibrates, the magnetic core shifts, altering the magnetic flux within the induction coil and generating an induced electromotive force. Other types include the piezoelectric ceramic type, where the ceramic inside generates a weak electrical signal when the engine vibrates, which is why the connecting wires of most knock sensors are shielded.