DTC P0325: Knock Sensor Circuit Malfunction

NOTE: Before you troubleshoot, record all freeze data and any on-board snapshot, and review GENERAL TROUBLESHOOTING INFORMATION .

Turn the ignition switch to ON (II).
Clear the DTC with the HDS.
Start the engine. Hold the engine speed at 3, 000 rpm without load (A/T in P or N, M/T in neutral) until the radiator fan comes on.
Hold the engine speed between 3, 000-4, 000 rpm for at least 10 seconds.
Check for Pending or Confirmed DTCs with the HDS.
Is DTC P0325 indicated?

YES: Go to step 6.

NO: Intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at the knock sensor and the ECM/PCM.
Turn the ignition switch to LOCK (0).
Jump the SCS line with the HDS.
Disconnect the knock sensor 1P connector (see KNOCK SENSOR REPLACEMENT ).
Disconnect ECM/PCM connector C (49P).
Check for continuity between ECM/PCM connector terminal C46 and body ground.
Is there continuity?

YES: Repair short in the wire between the ECM/PCM (C46) and the knock sensor, then go to step 14.

NO: Go to step 11.

Fig 1: Checking Continuity Between ECM/PCM Connector Terminal C46 & Body Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Connect the knock sensor 1P connector terminal to body ground with a jumper wire.

Fig 2: Connecting Knock Sensor 1P Connector Terminal To Body Ground With Jumper Wire
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Check for continuity between ECM/PCM connector terminal C46 and body ground.
Is there continuity?

YES: Go to step 13.

NO: Repair open in the wire between the ECM/PCM (C46) and the knock sensor, then go to step 14.

Fig 3: Checking Continuity Between ECM/PCM Connector Terminal C46 & Body Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Replace the knock sensor (see KNOCK SENSOR REPLACEMENT ).
Reconnect all connectors.
Turn the ignition switch to ON (II).
Reset the ECM/PCM with the HDS.
Do ECM/PCM IDLE LEARN PROCEDURE .
Hold the engine speed between 3, 000-4, 000 rpm or at least 10 seconds.
Check for Pending or Confirmed DTCs with the HDS.
Is DTC P0325 indicated?

YES: Go to step 21.

NO: Go to step 20.
Monitor the OBD STATUS for DTC P0325 in the DTCs MENU with the HDS.
Does the screen indicate PASSED?

YES: Troubleshooting is complete. If any other Pending or Confirmed DTCs were indicated in step 19, go to the indicated DTC's troubleshooting.

NO: If the HDS indicates FAILED, check for poor connections or loose terminals at the knock sensor and the ECM/PCM, then go to step 1. If the HDS indicates NOT COMPLETED, go to step 18 and recheck.
Update the ECM/PCM if it does not have the latest software (see ECM/PCM UPDATE ), or substitute a known-good ECM/PCM (see SUBSTITUTING THE ECM/PCM ).
Hold the engine speed between 3, 000-4, 000 rpm for at least 10 seconds.
Check for Pending or Confirmed DTCs with the HDS.
Is DTC P0325 indicated?

YES: Check for poor connections or loose terminals at the knock sensor and the ECM/PCM. If the ECM/PCM was updated, substitute a known-good ECM/PCM (see SUBSTITUTING THE ECM/PCM ), then go to step 22. If the ECM/PCM was substituted, go to step 1.

NO: Go to step 24.
Monitor the OBD STATUS for DTC P0325 in the DTCs MENU with the HDS.
Does the screen indicate PASSED?

YES: If the ECM/PCM was updated, troubleshooting is complete. If the ECM/PCM was substituted, replace the original ECM/PCM (see ECM/PCM REPLACEMENT ). If any other Pending or Confirmed DTCs were indicated in step 23, go to the indicated DTC's troubleshooting.

NO: If the HDS indicates FAILED, check for poor connections or loose terminals at the knock sensor and the ECM/PCM. If the ECM/PCM was updated, substitute a known-good ECM/PCM (see SUBSTITUTING THE ECM/PCM ), then go to step 22. If the ECM/PCM was substituted, go to step 1. If the HDS indicates NOT COMPLETED, go to step 22.