Suzuki XL7 2007 Service Manual page 208

1A-103 Engine General Information and Diagnosis:
DTC P0326, P0327, P0328, P0331, P0332, or
P0333
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 P0326: Knock Sensor (KS) System Performance
Bank 1
DTC P0327: Knock Sensor (KS) Circuit Low Voltage
Bank 1
DTC P0328: Knock Sensor (KS) Circuit High Voltage
Bank 1
DTC P0331: Knock Sensor (KS) System Performance
Bank 2
DTC P0332: Knock Sensor (KS) Circuit Low Voltage
Bank 2
DTC P0333: Knock Sensor (KS) Circuit High Voltage
Bank 2
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.
In order to differentiate between normal engine noise
and spark knock, the ECM samples the KS signal. The
ECM samples the KS signal for a certain length of time
under different engine speeds and loads during non-
cylinder knock events. This sampling is used to
determine a range of acceptable normal engine noise.
Conditions for Running the DTCs
P0326 and P0331
• Before the ECM can report DTC P0326 or P0331
failed, DTCs P0324, P0335, P0336, and P0338 must
run and pass.
• DTCs P0341, P0342, P0343, P0346, P0347, P0348,
P0366, P0367, P0368, P0391, P0392, and P0393 are
not set.
• The engine coolant temperature (ECT) sensor is more
than 60°C (140°F).
• The engine speed is greater than 2,200 RPM.
• DTCs P0326 and P0331 run continuously once the
above conditions are met for approximately 20
seconds.
P0327, P0328, P0332, and P0333
• Before the ECM can report DTC P0327 P0328,
P0332, or P0333 failed, DTCs P0324, P0335, P0336,
and P0338 must run and pass.
• DTCs P0341, P0342, P0343, P0346, P0347, P0348,
P0366, P0367, P0368, P0391, P0392, and P0393 are
not set.
• The engine coolant temperature (ECT) sensor is
greater than 60°C (140°F).
• The increase in engine speed is less than a range of
1,500-2,500 RPM per second.
• The increase in engine load is less than a range of 50-
100 kPa per second.
• DTCs P0327, P0328, P0332, and P0332 run
continuously once the above conditions are met for
approximately 20 seconds.
Conditions for Setting the DTCs
P0326 and P0331
The ECM detects a KS signal voltage that is not in the
range of a predetermined engine noise level in 25 of 250
test samples. The condition exists for greater than 4
seconds or for a cumulative of 50 seconds.
P0327 or P0332
The ECM detects a KS signal voltage that is less than
the predetermined minimum engine noise level for
greater than 4 seconds or for a cumulative of 50
seconds.
P0328 or P0333
The ECM detects the KS signal voltage is greater than
predetermined maximum engine noise level for greater
than 4 seconds or for a cumulative of 50 seconds.
Action Taken When the DTC Sets
DTCs P0326, P0327, P0328, P0331, P0332, and P0333
are Type B DTCs.
Conditions for Clearing the DTC
DTCs P0326, P0327, P0328, P0331, P0332, and P0333
are Type B DTCs.