SFI SYSTEM, Diagnostic DTC:P032511

DTC Code DTC Name
P032511 Knock Sensor 1 Bank 1 or Single Sensor Circuit Short to Ground

DESCRIPTION

A flat-type knock control sensor (non-resonant type) has a structure that can detect vibrations between approximately 5 kHz and 15 kHz.

The knock control sensor is fitted onto the engine block to detect engine knocking.

The knock control 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
P032511 The knock control sensor output voltage is less than 0.5 V for 1 second or more (1 trip detection logic).

  • Short in knock control sensor circuit

  • Knock control sensor

  • ECM

Tech Tips

When DTC P032511 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 engine switch is turned off.

Reference: Inspection using an oscilloscope

B000JFDE01

Tech Tips

The correct waveform is as shown.

ECM Terminal Name Between KNK1 and EKNK
Tester Range 1 V/DIV., 1 ms./DIV.
Condition Engine speed maintained at 4000 rpm after warming up engine

MONITOR DESCRIPTION

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

MONITOR STRATEGY

Frequency of Operation Continuous

CONFIRMATION DRIVING PATTERN


  1. Connect the GTS to the DLC3.

  2. Turn the engine switch on (IG) and turn the GTS on.

  3. Clear the DTCs (even if no DTCs are stored, perform the clear DTC procedure).

  4. Turn the engine switch off and wait for at least 30 seconds.

  5. Turn the engine switch on (IG) and turn the GTS on.

  6. Start the engine and wait 5 minutes.

  7. Enter the following menus: Powertrain / Engine / Trouble Codes.

  8. Read the pending DTCs.

    Tech Tips


    • If a pending DTC is output, the system is malfunctioning.

    • If a pending DTC is not output, perform the following procedure.

  9. Enter the following menus: Powertrain / Engine / Utility / All Readiness.

  10. Input the DTC: P032511.

  11. Check the DTC judgment result.

    GTS Display Description
    NORMAL

    • DTC judgment completed

    • System normal
    ABNORMAL

    • DTC judgment completed

    • System abnormal
    INCOMPLETE

    • DTC judgment not completed

    • Perform driving pattern after confirming DTC enabling conditions
    N/A

    • Unable to perform DTC judgment

    • Number of DTCs which do not fulfill DTC preconditions has reached ECU memory limit

    Tech Tips


    • If the judgment result shows NORMAL, the system is normal.

    • If the judgment result shows ABNORMAL, the system has a malfunction.

    • If the judgment result shows INCOMPLETE or N/A, idle the engine for 5 minutes and check the DTC judgment result again.

WIRING DIAGRAM

B000M28E06

INSPECTION PROCEDURE

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. CHECK TERMINAL VOLTAGE (POWER SOURCE OF KNOCK CONTROL SENSOR)


    1. B000LVXE09
      Text in Illustration
      *a

      Front view of wire harness connector

      (to Knock Control Sensor)

      Disconnect the knock control sensor connector.

    2. Turn the engine switch on (IG).

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      G1-2 - G1-1 Engine switch on (IG) 4.5 to 5.5 V

    NG

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

    OK

  2. INSPECT KNOCK CONTROL SENSOR


    1. Inspect the knock control sensor Click here.

      Tech Tips

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


    OK

    CHECK WHETHER DTC OUTPUT RECURS (DTC P032511) Click here

    NG

    REPLACE KNOCK CONTROL SENSOR Click here

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


    1. Disconnect the knock control sensor connector.

    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
      G1-2 or E96-124 (KNK1) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  4. CHECK WHETHER DTC OUTPUT RECURS (DTC P032511)


    1. Connect the GTS to the DLC3.

    2. Turn the engine switch on (IG).

    3. Turn the GTS on.

    4. Clear the DTCs.

    5. Turn the engine switch off and wait for at least 30 seconds.

    6. Turn the engine switch on (IG).

    7. Turn the GTS on.

    8. Drive the vehicle in accordance with the driving pattern described in Confirmation Driving Pattern.

    9. Enter the following menus: Powertrain / Engine / Trouble Codes.

    10. Read the DTCs.

      Result
      Result Proceed to
      DTCs are not output A
      DTC P032511 is output B

    B

    REPLACE ECM Click here

    A

    CHECK FOR INTERMITTENT PROBLEMS Click here