DTC P0325: Knock Sensor Circuit Malfunction

Reset the ECM/PCM (see HOW TO RESET THE ECM/PCM ).
Start the engine. Hold the engine at 3,000 RPM with no load (in Park or neutral) until the radiator fan comes on, then let it idle.
Hold the engine at 3,000-4,000 RPM for at least 60 seconds.
Is DTC P0325 indicated?
1. YES - Go to step 4.
2. NO - Intermittent failure, system is OK at this time. Check for poor connections or loose wires at the knock sensor and at the ECM/PCM.
Turn the ignition switch OFF.
Disconnect the knock sensor 3P connector.
Turn the ignition switch ON (II).
Measure voltage between the knock sensor 3P connector terminal No. 1 and body ground.

Fig 1: Measuring Voltage Between Knock Sensor 3-Pin Connector Terminal No. 1 & Body Ground

Is there about 5 V?
1. YES - Go to step 12.
2. NO - Go to step 8.
Measure voltage between ECM/PCM connector terminal A9 and body ground.

Fig 2: Measuring Voltage Between ECM/PCM Connector Terminal A9 & Body Ground

Is there about 5 V?
1. YES - Repair open in the wire between the ECM/PCM (A9) and the knock sensor.
2. NO - Go to step 9.
Turn the ignition switch OFF.
Disconnect ECM/PCM connector A (31P).
Check for continuity between ECM/PCM connector terminal A9 and body ground.

Fig 3: Checking Continuity Between ECM/PCM Connector Terminal A9 & Body Ground

Is there continuity?
1. YES - Repair short in the wire between the ECM/PCM (A9) and the knock sensor.
2. NO - Reprogram the ECM/PCM if it does not have the latest software, or substitute a known-good ECM/PCM, then recheck (see ECM/PCM REPROGRAMMING AND SUBSTITUTION FOR TESTING ). If the symptom/indication goes away with a known-good ECM/PCM, replace the original ECM/PCM.
Substitute a known-good knock sensor and recheck.
Is DTC P0325 indicated?
1. YES - Reprogram the ECM/PCM if it does not have the latest software, or substitute a known-good ECM/PCM, then recheck (see ). If the symptom/indication goes away with a known-good ECM/PCM, replace the original ECM/PCM.
2. NO - Replace the original knock sensor.