P0330
DTC P0325-P0328, P0330, P0332, or P0333
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle (Diagnostic System Check - Vehicle) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (Strategy Based Diagnosis) for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions (Diagnostic Procedure Instructions) provides an overview of each diagnostic category.
DTC Descriptors
DTC P0325
- Knock Sensor Circuit Bank 1
DTC P0326
- Knock Sensor Performance
DTC P0327
- Knock Sensor Circuit Low Bank 1
DTC P0328
- Knock Sensor Circuit High Bank 1
DTC P0330
- Knock Sensor Circuit Bank 2
DTC P0332
- Knock Sensor Circuit Low Bank 2
DTC P0333
- Knock Sensor Circuit High Bank 2
Diagnostic Fault Information
Circuit/System Description
The knock sensor system enables the engine control module (ECM) to control the ignition timing for the best possible performance, while protecting the engine from potentially damaging levels of detonation. The sensors are located below each cylinder head on the engine block. The knock sensor produces an AC voltage signal that varies depending on the vibration level during engine operation. The ECM adjusts the spark timing based on the amplitude and the frequency of the knock sensor signal. The ECM receives the knock sensor signal through 2 isolated signal circuits. The ECM learns a minimum knock sensor noise level at idle and uses calibrated values for the rest of the RPM range. The ECM should monitor a normal knock sensor signal within the noise channel.
Conditions for Running the DTC
P0325, P0330, and P0326
* Engine Speed is greater than 1,800 RPM
* Manifold absolute pressure (MAP) is greater than 55 kPa
* The DTCs run continuously when the above conditions are met.
P0327, P0328, P0332, and P0333
* The ignition is ON.
* The DTCs run continuously when the above condition is met.
Conditions for Setting the DTC
P0325 and P0330
The knock sensor signal circuits are open or shorted together for 5 s.
P0326
* The knock sensor signal indicates an excessive engine knock is present.
* The ECM has commanded the spark retard to a value, which is greater than the calibrated value, for a specific engine load and speed.
* The above conditions exist for greater than 5 s.
P0327, P0328, P0332, and P0333
The knock sensor signal circuits are shorted to voltage or ground.
Action Taken When the DTC Sets
DTCs P0325, P0326, P0327, P0328, P0330, P0332 and P0333 are Type B DTCs.
Conditions for Clearing the DTC
DTCs P0325, P0326, P0327, P0328, P0330, P0332 and P0333 are Type B DTCs.
Diagnostic Aids
* Inspect the knock sensor for physical damage. A knock sensor that is dropped or damaged may cause a DTC to set.
* Inspect the knock sensor for proper installation. A knock sensor that is loose or over torqued may cause a DTC to set. The knock sensor should be free of thread sealant.
* The knock sensor mounting surface should be free of burrs, casting flash, and foreign material.
Reference Information
Schematic Reference
Engine Controls Schematics ([1][2]Electrical Diagrams)
Connector End View Reference
Component Connector End Views (Connector End Views By Name)
Electrical Information Reference
* Circuit Testing (Circuit Testing)
* Connector Repairs (Connector Repairs)
* Testing for Intermittent Conditions and Poor Connections (Testing for Intermittent Conditions and Poor Connections)
* Wiring Repairs (Wiring Repairs)
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions (Powertrain Diagnostic Trouble Code (DTC) Type Definitions)
Scan Tool Reference
Control Module References (Programming and Relearning)for scan tool information
Circuit/System Testing
P0325, P0327, P0328, P0330, P0332, P0333
1. Ignition ON, engine OFF.
2. Disconnect the knock sensor harness connector.
3. Measure for 2-3 V between each of the following circuits and ground on the ECM side of the harness connector:
* The knock sensor signal circuit, terminal A
* The knock sensor signal circuit, terminal B
• If less than the specified range, test the circuits for a short to ground or an open/high resistance. If the circuits test normal, replace the ECM.
• If greater than the specified range, test the circuits for a short to voltage. If the circuits test normal, replace the ECM.
4. If the circuits test normal, replace the knock sensor.
P0326
* If DTC P0335 or P0336 are also set, diagnose those DTCs first.
* Inspect for a loose or broken vehicle accessory or accessory bracket.
* Inspect for excessive engine mechanical noise.
Component Testing
1. Connect the DMM between the knock sensor signal circuit terminal A and the knock sensor signal circuit terminal B on the sensor side of the knock sensor harness connector.
2. Set the DMM to the 400 mV AC hertz scale and wait for the DMM to stabilize at 0 Hz.
Note: DO NOT tap on plastic engine components.
3. Tap on the engine block with a non-metallic object near the knock sensor while observing the signal indicated on the DMM.
4. The DMM should display a fluctuating frequency while tapping on the engine block.
Repair Instructions
Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.
* Knock Sensor Replacement - Bank 1 (Knock Sensor Replacement - Bank 1)
* Knock Sensor Replacement - Bank 2 (Knock Sensor Replacement - Bank 2)
* Symptoms - Engine Controls (Symptoms - Engine Controls)
* Symptoms - Engine Mechanical (Symptoms - Engine Mechanical)
* Control Module References (Programming and Relearning)for ECM replacement, setup, and programming