P0326
DTC P0324, P0326, or P06B6 (LUW)
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 P0324
- Knock Sensor Module Performance
DTC P0326
- Knock Sensor Performance
DTC P06B6
- Control Module Knock Sensor Processor 1 Performance
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 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 for all of the RPM range. The ECM monitors for a normal knock sensor signal. The ECM generates a 20 KHz signal on the output circuit and monitors that it is sent back and detected on the return circuit. The ECM processes the return signal to verify the internal knock sensor processor.
Conditions for Running the DTC
P0324 Excessive Knock Detection Mode
* The engine speed is between 1 000-8 500 RPM.
* The engine is running for greater than 0.8 s.
* The ECT is greater than -40°C (-40°F).
* The IAT is greater than -40°C (-40°F).
* The DTCs run continuously when the above conditions are met.
P0324 Abnormal Noise Detection Mode
* The engine speed is less than 8 500 RPM.
* The engine is running for greater than 0.4 s.
* The ECT is greater than -40°C (-40°F).
* The IAT is greater than -40°C (-40°F).
* The DTCs run continuously when the above conditions are met.
P0326 Excessive Knock Detection Mode
* Engine speed is between 1 000-8 500 RPM.
* The engine is running for greater than 3 s.
* The ECT is greater than -40°C (-40°F).
* The IAT is greater than -40°C (-40°F).
* The DTCs run continuously when the above conditions are met.
P0326 Abnormal Noise Detection Mode
* The engine speed is greater than 3 500-8 500 RPM.
* The engine is running for greater than 0.9 s.
* The ECT is greater than -40°C (-40°F).
* The IAT is greater than -40°C (-40°F).
* The DTCs run continuously when the above conditions are met.
P06B6
* Engine speed is between 600-4 250 RPM.
* The engine is running for greater than 5 s.
* The DTC runs continuously when the above conditions are met.
Conditions for Setting the DTC
P0324
The ECM detects that the knock sensor signal performance is out of the normal expected range due to an excessive engine knock or abnormal engine noise on a per cylinder basis.
P0326
The ECM detects that the knock sensor signal performance is out of the normal expected range due to an excessive engine knock or abnormal engine noise on a per bank basis.
P06B6
The ECM has detected an internal knock sensor processor fault.
Action Taken When the DTC Sets
* DTCs P0324, P0326 and P06B6 are Type B DTCs.
* The ignition timing is retarded to reduce the potential of engine damaging spark knock.
Conditions for Clearing the DTC
DTCs P0324, P0326 and P06B6 are Type B DTCs.
Diagnostic Aids
* Inspect the knock sensor for physical damage and proper installation. 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 Fuel Pump and Level Sensor Assembly
Description and Operation
Electronic Ignition System Description Description and Operation
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 Control Module References for scan tool information
Circuit/System Testing
1. Engine idling, observe the DTC information with a scan tool. Verify DTC P0325, P0327, P0328, and P06B6 is not set.
• If DTC P0325, P0327, or P0328 is set with P06B6, refer to DTC P0325, P0327, or P0328 (LUW) P0325 for further diagnosis.
• If only DTC P06B6 is set and no external knock sensor circuit issues exist, - replace the K20 Engine Control Module.
2. Ignition OFF, inspect for the conditions listed below:
* The B68 Knock Sensor for physical damage. A B68 Knock Sensor that is dropped or damaged may cause a DTC to set.
* The B68 Knock Sensor for proper installation. A B68 Knock Sensor that is loose or over torqued may cause a DTC to set.
* The B68 Knock Sensor should be free of thread sealant. The B68 Knock Sensor mounting surface should be free of burrs, casting flash, and foreign material.
* The B68 Knock Sensor must be clear of hoses, brackets, and engine electrical wiring.
* For loose accessory brackets
* Inspect for serpentine belt and tensioner wear.
* Inspect for an engine mechanical condition Symptoms - Engine Mechanical Symptoms - Engine Mechanical.
• If a condition is found, repair as necessary.
3. If there is no mechanical condition, test or replace the B68 Knock Sensor.
4. Operate the vehicle within the conditions for running the DTC to verify the DTC does not reset. You may also operate the vehicle within the conditions that you observed from the freeze frame/failure records data.
Repair Instructions
Perform the Diagnostic Repair Verification Verification Tests after completing the repair.
* Knock Sensor Replacement Service and Repair
* Control Module References Control Module References for ECM replacement, programming and setup.