P0330
DTC P0330 Knock Sensor 2 Circuit Malfunction (Bank 2)CIRCUIT DESCRIPTION
DTC Detecting Condition:
Each knock sensor is fitted to the right bank and left bank of the cylinder block to detect engine knocking. This sensor contains a piezoelectric element which generates a voltage when it becomes deformed. The piezoelectric element sends a signal to the ECM, when the cylinder block vibrates due to knocking. If engine knocking occurs, ignition timing is retarded to suppress it.
Reference: INSPECTION USING OSCILLOSCOPE
- With the engine racing (4,000 rpm), check the waveform between terminals KNK1, KNK2 of the ECM connector and the body ground.
HINT: The correct waveform is as shown in the illustration.
- Spread the time on the horizontal axis, and confirm that a period of the wave is 0.141 msec. (Normal mode vibration frequency of knock sensor: 7.1 kHz).
HINT: If the normal mode vibration frequency is not 7.1 kHz, the sensor is malfunctioning.
MONITOR DESCRIPTION
Monitor Strategy:
Typical Enabling Conditions:
Typical Malfunction Thresholds:
The knock sensor located on the cylinder block detects spark knock.
When spark knock occurs, the sensor pick-up vibrates in a specific frequency range. When the ECM detects the voltage in this frequency range, it retards the ignition timing to suppress the spark knock.
The ECM also senses background engine noise with the knock sensor and uses this noise to check for faults in the sensor. If the knock sensor signal level is too low for more than 10 sec., and if the knock sensor output voltage is out of the normal range,the ECM interprets this as a fault in the knock sensor and sets a DTC.
Wiring Diagram:
INSPECTION PROCEDURE
Step 1 - 3:
Step 4:
HINT:
- DTC P0325 is for the front side knock sensor circuit.
- DTC P0330 is for the rear side knock sensor circuit.
- Read freeze frame data using hand-held tester or OBD II scan tool. Because freeze frame data records the engine conditions when a malfunction is detected. When troubleshooting, it is useful for determining whether the vehicle was running or stopped, the engine was warmed up or not, the air-fuel ratio was lean or rich, etc. when a malfunction occurred.