Technical Description of OBD-II Trouble Code
The knock sensor 1 circuit is experiencing a high input, either in Bank 1 or in a single sensor.
What does that mean?
This diagnostic trouble code (DTC) is a generic powertrain code that is applicable to vehicles equipped with OBD-II. Although it is a generic code, the specific repair steps may vary depending on the make and model of the vehicle.
Knock sensors are used to detect engine pre-detonation, also known as engine knock or ping. The knock sensor (KS) is typically a two-wire sensor that receives a 5-volt reference from the sensor and sends a signal back to the PCM (powertrain control module).
The sensor signal wire informs the PCM when a knock occurs and the severity of the knock. The PCM will adjust the spark timing to prevent pre-detonation. Most PCMs have the capability to learn spark knock trends during normal engine operation.
A P0328 code is a generic DTC that applies to all vehicle makes and refers to a high output voltage from the knock sensor. In many cases, this means the voltage is above 4.5V, but the specific value depends on the make and model of the vehicle. This code specifically refers to the sensor on bank #1.
Symptoms
Symptoms of a P0328 DTC may include:
Causes
Potential causes of a P0328 code include:
Possible Solutions
If you can hear engine knock (detonation), the first step is to address the mechanical problem causing the knock and then retest. Ensure that the correct octane fuel is being used (some engines require premium fuel, so check the owner’s manual). Apart from that, for this code, the problem is most likely either with the knock sensor itself or with the wiring and connectors between the sensor and the PCM.
Realistically, for DIY vehicle owners, the best next steps are to measure the resistance between the two knock sensor wire terminals where they connect to the PCM. Also, check the voltage of the same terminals and compare those numbers to the manufacturer’s specifications. Additionally, inspect all wiring and connectors leading from the knock sensor to the PCM. Furthermore, use a Digital Volt Ohm Meter (DVOM) to measure the resistance of the knock sensor itself and compare it to the vehicle manufacturer’s specification. If the knock sensor resistance value is out of spec, it needs to be replaced.
Other knock sensor DTCs include P0324, P0325, P0326, P0327, P0328, P0329, P0330, P0331, P0332, P0334
