2010 Cadillac CTS Sedan AWD V6-3.6L Page 832
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 greater than -40掳C (-40掳F).
* The intake air temperature (IAT) is greater than -40掳C (-40掳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 2,200-8,500 RPM.
* The ECT is greater than -40掳C (-40掳F).
* The IAT is greater than -40掳C (-40掳F).
* The DTCs run continuously when the above conditions are met.
P0325, P0327, P0328, P0330, P0332, and P0333
* Engine speed is between 400-8,500 RPM.
* The ECT is greater than -40掳C (-40掳F).
* The IAT is greater than -40掳C (-40掳F).
* The DTCs run continuously when the above conditions are met.
P06B6 and P06B7
* Engine speed is between 400-4,000 RPM.
* The ECT is greater than -40掳C (-40掳F).
* The IAT is greater than -40掳C (-40掳F).
* The DTCs run continuously when the above conditions are met.
Conditions for Setting the DTC
P0324
The knock sensor signal indicates an excessive engine knock is present for greater than 10 s for at least 1 single cylinder.
P0325 and P0330
The knock sensor signal circuits are open for greater than 10 s.
P0326 and P0331
* The signal indicates the sensor harness is connected but the sensor is not properly bolted to the engine.
OR
* The knock sensor signal indicates an excessive engine knock is present in an entire bank.
* Either of the above conditions exist for greater than 10 s.
P0327 and P0332
The knock sensor signal circuits are shorted to ground for greater than 10 s.
P0328 and P0333
The knock sensor signal circuits are shorted to voltage for greater than 10 s.
P06B6 and P06B7
The ECM has detected an internal knock sensor processor fault.
Action Taken When the DTC Sets
* DTCs P0324, P0325, P0326, P0327, P0328, P0330, P0331, P0332 P0333, P06B6, and P06B7 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, P0325, P0326, P0327, P0328, P0330, P0331, P0332 P0333, P06B6, and P06B7 are Type B DTCs.
