What this code means
P0328 means the PCM may be seeing a knock sensor circuit signal that is higher than expected.
What the vehicle may do
- The vehicle may have a check engine light.
- It can feel normal, or it may have reduced performance depending on PCM response.
- Ignition timing behavior may be altered while the fault is present.
Possible fault areas
- Possible knock sensor issue.
- Possible open or poor connection in the knock sensor signal circuit.
- Possible open or poor connection in the knock sensor ground circuit.
- Possible connector or terminal condition at the knock sensor or PCM.
- Possible PCM software or PCM-related issue after circuit checks pass.
Diagnostic path
Opening context
On this 2010 to 2016 Honda CR-V with the 2.4 gas engine, P0328 points to a high-voltage condition on the knock sensor circuit. In plain terms, the PCM may be seeing a knock sensor signal that is higher than expected. The driver may only notice a check engine light, but the vehicle can also feel down on power or have altered ignition timing behavior depending on how the PCM responds. Broadly, this can involve the knock sensor itself, the knock sensor signal line, the sensor ground side, connector or terminal issues, or, after the circuit checks pass, a possible PCM software or PCM-related fault area. Before getting deep into testing, start with the basic system checks and follow a structured diagnostic approach.
Verify the problem first
Start by verifying whether the fault is active. Turn the vehicle to ON, clear the code with the HDS, turn the vehicle OFF, then turn it back ON and check for pending or confirmed codes with the HDS. If P0328 comes right back, the failure is duplicated and you move into circuit testing. If it does not come back, treat it as intermittent for now. At that point, the system is OK at this time, so check for poor connections or loose terminals at the knock sensor and at the PCM. If captured data is available for this event, try to reproduce the captured conditions instead of guessing.
Check the knock sensor connector voltage
With the failure duplicated, turn the vehicle OFF and disconnect the knock sensor 2P connector. Turn the vehicle back ON. Measure voltage between terminal No. 1 and terminal No. 2 at the disconnected knock sensor connector. The decision point here is whether you have about 5.0 V. If you do, the path calls for replacing the knock sensor. If you do not have about 5.0 V, keep the connector disconnected and continue to the next voltage check.
Separate the signal side from the ground side
Next, measure voltage from knock sensor connector terminal No. 1 to body ground, still with the vehicle ON and the knock sensor connector disconnected. Again, the decision point is about 5.0 V. If terminal No. 1 to body ground shows about 5.0 V, the signal side has the expected feed at that point, so the next check is the KS GND line. If terminal No. 1 to body ground does not show about 5.0 V, move to the KNOCK line open-wire check.
Check the KNOCK line for an open
For the KNOCK line check, turn the vehicle OFF. Jump the SCS line with the HDS and wait more than 1 minute. Then disconnect PCM connector C, the 51P connector. With the vehicle OFF, the knock sensor connector disconnected, and PCM connector C disconnected, check continuity between knock sensor connector terminal No. 1 and PCM connector C terminal No. 29. If there is continuity, the KNOCK wire is OK. At that point, update the PCM if it does not have the latest software, or substitute a known-good PCM, then recheck. If P0328 goes away after the PCM was updated, troubleshooting is complete. If P0328 goes away with a substituted PCM, replace the original PCM. If there is no continuity, repair the open in the KNOCK wire between PCM C29 and the knock sensor.
Check the KS GND line for an open
If the earlier voltage check sent you to the KS GND side, the setup is similar. Turn the vehicle OFF, jump the SCS line with the HDS, and wait more than 1 minute. Disconnect PCM connector C, the 51P connector. With the vehicle OFF, the knock sensor connector disconnected, and PCM connector C disconnected, check continuity between knock sensor connector terminal No. 2 and PCM connector C terminal No. 28. If continuity is present, the KS GND wire is OK. Update the PCM if it does not have the latest software, or substitute a known-good PCM, then recheck. If P0328 goes away after a PCM update, troubleshooting is complete. If it goes away with a substituted PCM, replace the original PCM. If there is no continuity, repair the open in the KS GND wire between PCM C28 and the knock sensor.
Close and repair check
The key is to keep the path clean: verify the code, check the sensor-side voltage, use the second voltage check to decide whether you are chasing the KNOCK line or the KS GND line, and only move toward PCM software or PCM substitution after the wiring path checks good. After any repair, verify the repair and confirm P0328 stays gone. For more diagnostic training, visit stepdiagnostics.com.
Final check
Follow the voltage checks first, then prove the signal and ground circuits before considering PCM software or PCM substitution.
For more guided automotive diagnostics, visit STEP Diagnostics.
