Kubota P0327 – Engine Control Module (ECM): Knock 1 Sensor Open or Not Present

The knock sensor circuit has an abnormally low input, an open circuit, or the sensor is entirely disconnected. The system triggers this fault when the engine is running and the knock sensor input voltage drops below 0.005 V, causing the engine to enter a Power Derate 1 state.

• WG1605
• WG2503
• WG3800

1. 1

   Check the knock sensor wiring harness for an open circuit or a short to ground.

2. 2

   Inspect the water-resistant ignition-system connectors for moisture, corrosion, or backed-out pins.

3. 3

   Verify that the ECM is supplying the correct 5-volt reference voltage to the sensor connector.

4. 4

   Verify continuity between the ECM connector pins and the knock sensor connector.

1. 1

   Power Down

   Turn off the engine and disconnect the battery negative terminal to prevent electrical spikes.

2. 2

   Locate the Sensor

   Locate the knock sensor, which is threaded directly into the engine block or cylinder head.

3. 3

   Disconnect & Inspect

   Unplug the electrical connector. If the connector is heavily corroded, clean it with contact cleaner and apply dielectric grease to deter capillary action. If the wiring is damaged, repair the sub-harness.

4. 4

   Remove the Sensor

   If the wiring passes all tests, use a socket to carefully unthread the faulty knock sensor from the block.

5. 5

   Install the New Sensor

   Thread the new OEM knock sensor into the block. The mounting surface must be completely clean. Torque strictly to OEM specifications to avoid crushing the internal piezoelectric element.

6. 6

   Reconnect

   Plug the water-resistant connector back into the sensor.

7. 7

   Clear Codes

   Reconnect the battery, connect your diagnostic tool, and clear the P0327 code. Run the engine above 2000 RPM to verify the code does not return.