SFI SYSTEM, Diagnostic DTC:P0327, P0328, P0332, P0333

DTC Code DTC Name
P0327 Knock Sensor 1 Circuit Low Input (Bank 1 or Single Sensor)
P0328 Knock Sensor 1 Circuit High Input (Bank 1 or Single Sensor)
P0332 Knock Sensor 2 Circuit Low Input (Bank 2)
P0333 Knock Sensor 2 Circuit High Input (Bank 2)

DESCRIPTION

Flat-type knock sensors (non-resonant type) have structures that can detect vibrations between approximately 5 kHz and 15 kHz.

2 knock sensors are fitted onto the engine block to detect engine knocking.

Each knock sensor contains a piezoelectric element which generates a voltage when it becomes deformed.

The voltage is generated when the engine block vibrates due to knocking. Any occurrence of engine knocking can be suppressed by delaying the ignition timing.

DTC No. DTC Detection Condition Trouble Area

P0327

P0332

 Output voltage of the knock sensor is below 0.5 V (1 trip detection logic).

  • Short in knock sensor circuit

  • Knock sensor

  • ECM

P0328

P0333

 Output voltage of the knock sensor is higher than 4.5 V (1 trip detection logic).

  • Open in knock sensor circuit

  • Knock sensor

  • ECM

Tech Tips

When DTC P0327, P0328, P0332 or P0333 is stored, the ECM enters fail-safe mode. During fail-safe mode, the ignition timing is delayed to its maximum retardation. The ECM continues operating in fail-safe mode until the ignition switch is turned off.

Reference: Inspection using an oscilloscope

B001Y1NE01
*a KNK1 Signal Waveform
*b 1 V/DIV.
*c 1 msec./DIV.

The correct waveform is as shown.

Item Content
Terminal

KNK1 - EKNK

KNK2 - EKN2
Equipment Setting

1 V/DIV.

0.01 to 1 msec./DIV.
Condition Engine speed at 4000 rpm with warm engine

MONITOR DESCRIPTION

If the output voltage transmitted by the knock sensor remains low or high for more than 1 second, the ECM interprets this as a malfunction in the sensor circuit and stores a DTC.

The monitor for DTCs P0327, P0328, P0332 and P0333 begins to run 5 seconds after the engine is started.

If the malfunction is not repaired successfully, DTC P0327, P0328, P0332 or P0333 is stored 5 seconds after the engine is next started.

WIRING DIAGRAM

B001Z2BE03
*a Knock Sensor (for Bank 1)
*b Shielded
*c Knock Sensor (for Bank 2)

CAUTION / NOTICE / HINT

Tech Tips


  • DTCs P0327 and P0328 are for the bank 1 knock sensor circuit.

  • DTCs P0332 and P0333 are for the bank 2 knock sensor circuit.

  • Read freeze frame data using the GTS. Freeze frame data records the engine condition when malfunctions are detected. When troubleshooting, freeze frame data can help determine if the vehicle was moving or stationary, if the engine was warmed up or not, if the air-fuel ratio was lean or rich, and other data from the time the malfunction occurred.

  • Bank 1 refers to the bank that includes the No. 1 cylinder*.

    *: The No. 1 cylinder is the cylinder which is farthest from the transmission.

  • Bank 2 refers to the bank that does not include the No. 1 cylinder.

PROCEDURE


  1. CHECK KNOCK SENSOR

    B001Y1AC01
    *a

    Front view of wire harness connector

    (to ECM)

    1. Disconnect the ECM connector.

    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      C45-94 (KNK1) - C45-93 (EKNK) 20°C (68°F) 120 to 280 kΩ
      C45-117 (KNK2) - C45-116 (EKN2) 20°C (68°F) 120 to 280 kΩ

    NG

    CHECK HARNESS AND CONNECTOR (KNOCK SENSOR - ECM) Click here

    OK

  2. CHECK TERMINAL VOLTAGE (ECM)

    B001YKUE02
    Text in Illustration
    *1 Female
    *a

    Front view of wire harness connector

    (to ECM Wire)

    1. Disconnect the CU1 connector.

    2. Turn the ignition switch to ON.

    3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      CU1 female connector 2 - 5 Ignition switch ON 4.5 to 5.5 V
      CU1 female connector 4 - 6 Ignition switch ON 4.5 to 5.5 V

    OK

    CHECK FOR INTERMITTENT PROBLEMS Click here

    NG

    REPLACE ECM Click here

  3. CHECK HARNESS AND CONNECTOR (KNOCK SENSOR - ECM)


    1. Disconnect the knock sensor connectors.

    2. Disconnect the ECM connector.

    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      U2-2 - C45-94 (KNK1) Always Below 1 Ω
      U2-1 - C45-93 (EKNK) Always Below 1 Ω
      U1-2 - C45-117 (KNK2) Always Below 1 Ω
      U1-1 - C45-116 (EKN2) Always Below 1 Ω
      U2-2 or C45-94 (KNK1) - Body ground Always 10 kΩ or higher
      U2-1 or C45-93 (EKNK) - Body ground Always 10 kΩ or higher
      U1-2 or C45-117 (KNK2) - Body ground Always 10 kΩ or higher
      U1-1 or C45-116 (EKN2) - Body ground Always 10 kΩ or higher

    OK

    REPLACE KNOCK SENSOR Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR