DTC P0325: Knock Sensor Circuit Malfunction

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

Turn the ignition switch ON (II).
Clear the DTC with the HDS.
Start the engine. Hold the engine speed at 3,000 rpm without load (in Park or neutral) until the radiator fan comes on, then let it idle.
Hold the engine speed at 3,000-4,000 rpm for at least 10 seconds.
Check for Temporary DTCs or DTCs with the HDS.
Is DTC P0325 indicated?
1. YES - Go to step 6.
2. NO - Intermittent failure, 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 OFF.
Jump the SCS line with the HDS.
Disconnect the knock sensor subharness 1P connector.
Disconnect ECM/PCM connector B (24P).
Check for continuity between ECM/PCM connector terminal B6 and body ground.

Fig 1: Checking Continuity Between ECM/PCM Connector Terminal B6 & Body Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there continuity?
1. YES - Repair short in the wire between the ECM/PCM (B6) and the knock sensor subharness, then go to step 19.
2. NO - Go to step 11.
Connect the knock sensor subharness 1P connector terminal to body ground with a jumper wire.

Fig 2: Connecting Knock Sensor Subharness 1P Connector Terminal To Body Ground With Jumper Wire
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Check for continuity between ECM/PCM connector terminal B6 and body ground.

Fig 3: Checking Continuity Between ECM/PCM Connector Terminal B6 & Body Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there continuity?
1. YES - Go to step 13.
2. NO - Repair open in the wire between the ECM/PCM (B6) and the knock sensor subharness, then go to step 19.
Remove the intake manifold (see REMOVAL ).
Disconnect the knock sensor 1P connector.
Check for continuity between the knock sensor subharness 1P connector terminal and body ground.

Fig 4: Checking Continuity Between Knock Sensor Subharness 1P Connector Terminal & Body Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there continuity?
1. YES - Repair short in the knock sensor subharness, then go to step 18.
2. NO - Go to step 16.
Check the knock sensor subharness for an open.
Is the subharness OK?
1. YES - Go to step 17.
2. NO - Repair open in the knock sensor subharness, then go to step 18.
Replace the knock sensor (see KNOCK SENSOR REPLACEMENT ).
Install the intake manifold (see INSTALLATION ).
Reconnect all connectors.
Turn the ignition switch ON (II).
Reset the ECM/PCM with the HDS.
Do the ECM/PCM IDLE LEARN PROCEDURE .
Hold the engine speed at 3,000-4,000 rpm for at least 10 seconds.
Check for Temporary DTCs or DTCs with the HDS.
Are any Temporary DTCs or DTCs indicated?
1. YES - If DTC P0325 is indicated, go to step 26. If any other Temporary DTCs or DTCs are indicated, go to the indicated DTCs troubleshooting.
2. NO - Go to step 25.
Monitor the OBD STATUS for DTC P0325 in the DTCs MENU with the HDS.
Does the screen indicate PASSED?
1. YES - Troubleshooting is complete.
2. NO - If the screen indicates FAILED, go to step 1. If the screen indicates NOT COMPLETED, go to step 22. and recheck.
Update the ECM/PCM if it does not have the latest software, or substitute a known-good ECM/PCM (see HOW TO TROUBLESHOOT CIRCUITS AT THE ECM/PCM ).
Hold the engine speed at 3,000-4,000 rpm for at least 10 seconds.
Check for Temporary DTCs or DTCs with the HDS.
Are any Temporary DTCs or DTCs indicated?
1. YES - If DTC P0325 is indicated, check for poor connections or loose terminals at the knock sensor and the ECM/PCM, then go to step 1. If any other Temporary DTCs or DTCs are indicated, go to the indicated DTCs troubleshooting.
2. NO - If the ECM/PCM was updated, troubleshooting is complete. If the ECM/PCM was substituted, replace the original ECM/PCM (see ECM/PCM REPLACEMENT ).