SFI SYSTEM, Diagnostic DTC:P0327 and 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

A390132E01

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
Tip:

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

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

A107909E17

CAUTION / NOTICE / HINT

Tip:

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.

      Tip:

      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.

    CHECK FOR INTERMITTENT PROBLEMS

    (Click here)

  2. INSPECT ECM (KNK1 VOLTAGE)

    1. U121192E02

      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

      F1-2 (KNK1) - F1-1 (E)

      Ignition switch ON

      4.5 to 5.5 V
      Table 1. Text in Illustration

      *a

      Front view of wire harness connector

      (to Knock Sensor)

    4. Reconnect the knock sensor connector.

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

  3. INSPECT KNOCK SENSOR

    1. Inspect the knock sensor (Click here).

      Tip:

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

    REPLACE ECM

    (Click here)

    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

      F1-2 (KNK1) - C111-122 (KNK1)

      Always

      Below 1 Ω

      F1-1 (E) - C111-121 (EKNK)

      Always

      Below 1 Ω

      Standard Resistance (Check for Short)

      Tester Connection

      Condition

      Specified Condition

      F1-2 (KNK1) or C111-122 (KNK1) - Body ground

      Always

      10 kΩ or higher

      F1-1 (E) or C111-121 (EKNK) - Body ground

      Always

      10 kΩ or higher

    4. Reconnect the knock sensor connector.

    5. Reconnect the ECM connector.

    REPLACE ECM

    (Click here)

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