Technical Definition:

Knock Sensor 1) Circuit High (Bank 1 or Single Sensor

Technical Description:

Knock sensors are used to detect engine pre-detonation (engine knock or ping). The knock sensor (KS) is usually a two wire sensor. A 5 volt reference is supplied to the sensor and there is a signal return from the knock sensor to the PCM (powertrain control module).

Possible Causes:

• Knock sensor connector is damaged
• Knock sensor circuit is open or shorted to ground
• Knock sensor circuit is shorted to voltage
• Knock sensor has failed
• Loose knock sensor
• Electrical interference in circuit
• Low fuel pressure
• Incorrect fuel octane
• Mechanical engine problem
• Failed/faulty PCM

Possible Symptoms:

• MIL (Malfunction Indicator Lamp) illumination
• Audible knocking from the engine compartment
• Pinging from engine under acceleration
• Loss of power
• Irregular RPM

Knock Sensor Circuit High Input

Possible Solutions:

OBD-II Trouble Code Type:

Diagnostic Step:

Tech Notes:

– Faulty knock sensor
– Knock sensor circuit poor electrical connection
– Knock sensor harness is open or shorted
– Faulty Engine Control Module (ECM)

Specific Makes:

– Possible Lack/Loss of Power