Suzuki XL7 2007 Service Manual page 207

DTC P0324
Diagnostic Instructions
• Perform the "Diagnostic System Check - Vehicle
Diagnostic Information: " prior to using this diagnostic
procedure.
• Review "Strategy Based Diagnosis: " for an overview
of the diagnostic approach.
• "Diagnostic Procedure Instructions - Vehicle
Diagnostic Information: " provides an overview of
each diagnostic category.
DTC Descriptors
DTC P0324: Knock Sensor (KS) Module Performance
Circuit/System Description
The knock sensor (KS) is a piezoelectric device that
produces an AC voltage of different amplitude and
frequency depending on the level of engine mechanical
vibration. The KS system monitors the knock sensor in
order to determine if detonation or spark knock is
present. If the KS system determines that excessive
knock is present, the engine control module (ECM)
retards the spark timing based on the signal from the KS
system. The KS 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 KS 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 KS 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 greater than 60°C
(140°F).
• DTC P0324 runs continuously once the above
conditions are met.
Engine General Information and Diagnosis:
Conditions for Setting the DTC
• The ECM detects an incorrect response to the self
tests performed on the internal KS circuitry.
• The condition exists for more than 4 seconds or for a
cumulative of 50 seconds.
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 (KS) System Description: "
DTC Type Reference
"Powertrain Diagnostic Trouble Code (DTC) Type
Definitions"
Scan Tool Reference
• "Scan Tool Data List - Engine Controls - 3.6L (LY7)"
• "Scan Tool Data Definitions - Engine Controls - 3.6L
(LY7)"
• "Scan Tool Output Controls - Engine Controls - 3.6L
(LY7)"
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. Observe and record the Freeze Frame/Failure
Records for DTC P0324.
➢ If DTC P0335, P0336, or P0338 also set, refer to
"DTC P0335, P0336, or P0338".
2. Clear the DTCs with a scan tool.
3. Turn OFF the ignition for 30 seconds.
4. Operate the vehicle within the Conditions for
Running the DTC. You may also operate the vehicle
within the conditions that you observed from the
Freeze Frame/Failure records. DTC P0324 should
not set.
➢ If DTC P0324 failed this ignition, replace the engine
control module (ECM).
Repair Instructions
Perform the "Diagnostic Repair Verification - Vehicle
Diagnostic Information: " after completing the diagnostic
procedure.
"Control Module References: " for engine control module
replacement, setup, and programming
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