SFI SYSTEM, Diagnostic DTC:P0327, P0328

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)

DESCRIPTION

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

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

The 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 The output voltage of the knock sensor is 0.5 V or less (1 trip detection logic).

  • Short in knock sensor circuit

  • Knock sensor

  • ECM
P0328 The output voltage of the knock sensor is 4.5 V or higher (1 trip detection logic).

  • Open in knock sensor circuit

  • Knock sensor

  • ECM

Tech Tips

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

Reference: Inspection using an oscilloscope

A0054FJE02
*a KNK1 Signal Waveform
*b 1 V/DIV.
*c 1 ms./DIV.

The correct waveform is as shown.

Item Content
Terminals KNK1 - EKNK
Equipment Settings

1 V/DIV.

1 ms./DIV.
Conditions Keep engine speed at 4000 rpm with warm engine

WIRING DIAGRAM

A0056T4E20
*a Knock Sensor
*b Shielded

CAUTION / NOTICE / HINT

Tech Tips

Read freeze frame data using the GTS. The ECM records vehicle and driving condition information as freeze frame data the moment a DTC is stored. 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.

PROCEDURE


  1. READ VALUE USING GTS (KNOCK FEEDBACK VALUE)


    1. Connect the GTS to the DLC3.

    2. Start the engine and turn the GTS on.

    3. Warm up the engine.

    4. Enter the following menus: Powertrain / Engine and ECT / Data List / Knock Feedback Value.

    5. Read the values displayed on the GTS while driving the vehicle.

      OK
      The values change.

      Tech Tips

      Malfunction does not occur Knock Feedback Value changes
      Malfunction occurs Knock Feedback Value does not change

      The Knock Feedback Value change can be confirmed by running the engine with a high load, for example, by activating the air conditioning system and racing the engine.


    OK

    CHECK FOR INTERMITTENT PROBLEMS Click here

    NG

  2. INSPECT ECM (KNK1 VOLTAGE)


    1. A0053XLE04
      Text in Illustration
      *a

      Front view of wire harness connector

      (to Knock Sensor)

      Disconnect the knock sensor 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
      C1-2 (KNK1) - C1-1 (EKNK) Ignition switch ON 4.5 to 5.5 V

    4. Reconnect the knock sensor connector.


    NG

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

    OK

  3. INSPECT KNOCK SENSOR


    1. Inspect the knock sensor Click here.

      Tech Tips

      Perform "Inspection After Repair" after replacing the knock sensor Click here.


    OK

    REPLACE ECM Click here

    NG

    REPLACE KNOCK SENSOR Click here

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


    1. Disconnect the knock sensor connector.

    2. Disconnect the ECM connector.

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

      Standard Resistance (Check for Open)
      Tester Connection Condition Specified Condition
      C1-2 (KNK1) - B53-122 (KNK1) Always Below 1 Ω
      C1-1 (EKNK) - B53-121 (EKNK) Always Below 1 Ω
      Standard Resistance (Check for Short)
      Tester Connection Condition Specified Condition
      C1-2 (KNK1) or B53-122 (KNK1) - Body ground Always 10 kΩ or higher
      C1-1 (EKNK) or B53-121 (EKNK) - Body ground Always 10 kΩ or higher

    4. Reconnect the knock sensor connector.

    5. Reconnect the ECM connector.


    OK

    REPLACE ECM Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR (ECM - KNOCK SENSOR)