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P0326




DTC P0324, P0326, P0331, P06B6, or P06B7 (LDK, LHU With Turbocharger) (2.0L With Turbocharger)

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 1 Performance

DTC P0331
- Knock Sensor 2 Performance

DTC P06B6
- Control Module Knock Sensor Processor 1 Performance

DTC P06B7
- Control Module Knock Sensor Processor 2 Performance

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 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 for each bank. 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 monitors the internal knock sensor processor by verifying a 20 KHz signal generated on the output circuit is detected on the return circuit.

Conditions for Running the DTC

P0324, P0326 and P0331-Excessive Knock Detection Mode
* Engine speed is between 400-8,500 RPM.
* The engine coolant temperature (ECT) is warmer than -40°C (-40°F).
* The intake air temperature (IAT) is warmer than -40°C (-40°F).
* The DTCs run continuously when the above conditions are met.

P0324, P0326 and P0331-Abnormal Noise Detection Mode-Improperly Bolted Knock Sensor
* Engine speed is between 2,000-8,500 RPM.
* The ECT is warmer than -40°C (-40°F).
* The IAT is warmer than -40°C (-40°F).
* The DTCs run continuously when the above conditions are met.

P06B6 and P06B7
* Engine speed is between 400-5,000 RPM.
* The ECT is warmer than -40°C (-40°F).
* The IAT is warmer than -40°C (-40°F).
* The DTCs run continuously when the above conditions are met.

Conditions for Setting the DTC

P0324

The ECM detects that the knock sensor signal indicates an excessive engine knock is present for greater than 8 s for at least 1 single cylinder.

P0326 and P0331
* The ECM detects that the knock sensor signal indicates the sensor harness is connected but the sensor is not properly bolted to the engine.
OR
* The ECM detects that the knock sensor signal indicates an excessive engine knock is present for more than 1 single cylinder.
* Either of the above conditions exist for greater than 8 s.

P06B6 and P06B7

The ECM has detected an internal knock sensor processor fault.

Action Taken When the DTC Sets

* DTCs P0324, P0326, P0331, P06B6, or P06B7 are Type B DTCs.
* The ignition timing is retarded to reduce the potential of engine damaging spark knock.

Conditions for Clearing the MIL/DTC

DTCs P0324, P0326, P0331, P06B6, or P06B7 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)
* Measuring Frequency (Measuring Frequency)

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 Verification

1. Engine at operating temperature, all accessories OFF, and engine speed greater than 2,000 RPM, observe the Knock Retard and Total Knock Retard parameters. The parameters should be 0°.
2. Engine idling, move the related harnesses and connectors for the KS circuits while observing the scan tool Knock Retard and Total Knock Retard parameters. The parameters should remain steady with no abrupt changes.
3. 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.

Circuit/System Testing

Note:
* Perform the Diagnostic System Check - Vehicle (Diagnostic System Check - Vehicle) prior to using these diagnostic procedures.
* If an engine mechanical noise can be heard, repair the condition before proceeding with this diagnostic. Refer to Symptoms - Engine Mechanical (Symptoms - Engine Mechanical).

P0324, P0326 and P0331
1. Using a scan tool, verify DTCs P0335 or P0336 are not set.

• If any of the DTCs are set, diagnose them first. Refer to Diagnostic Trouble Code (DTC) List - Vehicle (Diagnostic Trouble Code (DTC) List - Vehicle).

2. Verify the following conditions do not exist.

* A loose or broken vehicle accessory
* A loose or broken accessory bracket
* Excessive engine mechanical noise

• If any of the conditions exist, repair as necessary.

3. Replace the K20 ECM if no external knock sensor circuit issues exist.

P06B6 or P06B7
1. Using a scan tool, verify the following DTCs are not set: P0325, P0327, P0328, P0330, P0332, and P0333.

• If any of the DTCs are set, diagnose them first. Refer to Diagnostic Trouble Code (DTC) List - Vehicle (Diagnostic Trouble Code (DTC) List - Vehicle).

2. DTCs P06B6 and P06B7 indicate an internal ECM circuitry failure. Replace the K20 ECM if no external knock sensor circuit issues exist.

Repair Instructions

Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.

* Knock Sensor Replacement (Left Side) (Knock Sensor Replacement (Left Side))Knock Sensor Replacement (Right Side) (Knock Sensor Replacement (Right Side))
* Symptoms - Engine Mechanical (Symptoms - Engine Mechanical)
* Symptoms - Engine Controls (Symptoms - Engine Controls)
* Control Module References (Programming and Relearning) for ECM replacement, setup, and programming

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