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DTC P0324 (LAU)

DTC P0324 (LAU)

Diagnostic Instructions


• Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.

• Review Strategy Based Diagnosis for an overview of the diagnostic approach.

• Diagnostic Procedure Instructions provides an overview of each diagnostic category.


DTC Descriptors

DTC P0324

Knock Sensor Module Performance

Circuit/System Description

The knock sensor is a piezoelectric device that produces an AC voltage of different amplitude and frequency depending on the level of engine mechanical vibration. The knock sensor system monitors the knock sensor in order to determine if detonation or spark knock is present. If the knock sensor system determines that excessive knock is present, the engine control module (ECM) retards the spark timing based on the signal from the knock sensor system. The knock sensor produces an AC signal when specific frequencies are detected. The ECM then retards the timing until knock is controlled.

The ECM tests the functionality of the internal knock sensor signal evaluation circuitry. The knock sensor circuitry within the ECM is responsible for receiving, amplifying, filtering, and evaluating the AC voltage and frequency from the knock sensors. The ECM performs two tests that determine if the internal circuitry within the ECM is functioning correctly.

Test One

The ECM internally turns OFF the knock sensor signal circuits. The ECM then applies different test signals to the internal knock sensor circuitry to verify that each test signal output response is within range. If the ECM detects that any of the test signals are not within range, this DTC sets.

Test Two

The ECM internally turns OFF the knock sensor signal circuits. The ECM then tests for any output response when no test signals are applied. If the ECM detects an output response, this DTC sets.

Test Three

The ECM internally turns OFF the knock sensor signal circuits. The ECM generates an internal test pulse and monitors the return signal. If the return test pulse is less than a calibrated threshold, this DTC sets.

Conditions for Running the DTC


• The ECM is controlling spark.

• The engine coolant temperature is warmer than 45°C (113°F).

• DTC P0324 runs continuously once the above conditions are met.


Conditions for Setting the DTC


• The ECM detects an incorrect response to the self tests performed on the internal knock sensor circuitry.

• The condition exists for greater than 1 s or for a cumulative of 10 s.


Action Taken When the DTC Sets

DTCs P0324 is a Type B DTC.

Conditions for Clearing the DTC

DTCs P0324 is a Type B DTC.

Reference Information

Description and Operation

Knock Sensor System Description

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

Note

If you can hear an engine knock, repair the engine mechanical condition before proceeding with this diagnostic. Refer to Symptoms - Engine Mechanical .



1. Ignition ON, check the diagnostic trouble code (DTC) information with a scan tool. DTCs P0335, P0336 or P0338 should not set.

2. If DTC P0335, P0336, or P0338 is set, refer to Diagnostic Trouble Code (DTC) List - Vehicle for diagnosis of DTC P0335, P0336, or P0338.

3. Clear the DTCs with a scan tool.

4. Turn OFF the ignition for 30 s.

5. 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.

6. If DTC P0324 failed this ignition, replace the K20 ECM.


Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for Engine Control Module replacement, setup, and programming