СИСТЕМА ECD, Diagnostic DTC:P0651

DTC Code DTC Name
P0651 Sensor Reference Voltage "B" Circuit / Open

DESCRIPTION

DTC No. DTC Detection Condition Trouble Area
P0651

Power voltage (5 V as standard) supplied from ECM to throttle position sensor, accelerator pedal sensor and fuel pressure sensor (common rail assembly) are lower or higher than threshold.

(1 trip detection logic)

  • Diesel throttle body assembly (throttle position sensor)

  • Open or short in diesel throttle position sensor circuit

  • Accelerator pedal sensor assembly

  • Open or short in accelerator pedal sensor assembly circuit

  • Open or short in fuel pressure sensor (common rail assembly) circuit

  • Fuel pressure sensor (common rail assembly)

  • ECM

WIRING DIAGRAM

Refer to DTC P0122 Click here.

Refer to DTC P0192 Click here.

Refer to DTC P2122 Click here.

INSPECTION PROCEDURE

Note

When replacing the ECM, the ECM needs Registration and Initialization Click here.

Tech Tips


  • When the ECM must be replaced, before replacing the ECM, perform the "Learning Values Save" function using the GTS. Then after installing the new ECM, perform all of the initialization/registrations for the "Learning Values Write" function by following the instructions shown on the GTS display.

  • 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, and other data from the time the malfunction occurred.

PROCEDURE


  1. CHECK HARNESS AND CONNECTOR (DIESEL THROTTLE POSITION SENSOR - ECM)


    1. Disconnect the diesel throttle body assembly 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
      G1-1 (VC) - C84-83 (VCTA) Always Below 1 Ω
      G1-3 (VTA) - C84-117 (VTA1) Always Below 1 Ω
      G1-2 (E2) - C84-81 (ETA) Always Below 1 Ω
      G1-1 (VC) or C84-83 (VCTA) - Body ground Always 10 kΩ or higher
      G1-3 (VTA) or C84-117 (VTA1) - Body ground Always 10 kΩ or higher
      G1-2 (E2) or C84-81 (ETA) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR Click here

    OK

  2. CHECK HARNESS AND CONNECTOR (VC VOLTAGE)


    1. Disconnect the diesel throttle body assembly 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
      G1-1 (VC) - G1-2 (E2) Ignition switch ON 4.5 to 5.5 V

    NG

    REPLACE ECM Click here

    OK

  3. CHECK HARNESS AND CONNECTOR (ACCELERATOR PEDAL SENSOR ASSEMBLY - ECM)


    1. Disconnect the accelerator pedal position 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
      A2-1 (VCP2) - A76-29 (VCP2) Always Below 1 Ω
      A2-2 (EPA2) - A76-23 (EPA2) Always Below 1 Ω
      A2-3 (VPA2) - A76-43 (VPA2) Always Below 1 Ω
      A2-4 (VCPA) - A76-27 (VCPA) Always Below 1 Ω
      A2-5 (EPA) - A76-22 (EPA) Always Below 1 Ω
      A2-6 (VPA) - A76-52 (VPA) Always Below 1 Ω
      A2-1 (VCP2) or A76-29 (VCP2) - Body ground Always 10 kΩ or higher
      A2-2 (EPA2) or A76-23 (EPA2) - Body ground Always 10 kΩ or higher
      A2-3 (VPA2) or A76-43 (VPA2) - Body ground Always 10 kΩ or higher
      A2-4 (VCPA) or A76-27 (VCPA) - Body ground Always 10 kΩ or higher
      A2-5 (EPA) or A76-22 (EPA) - Body ground Always 10 kΩ or higher
      A2-6 (VPA) or A76-52 (VPA) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR Click here

    OK

  4. CHECK HARNESS AND CONNECTOR (VC VOLTAGE)


    1. Disconnect the accelerator pedal position sensor connector.

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

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      A2-4 (VCPA) - A2-5 (EPA) Ignition switch ON 4.5 to 5.5 V
      A2-1 (VCP2) - A2-2 (EPA2) Ignition switch ON 4.5 to 5.5 V

    NG

    REPLACE ECM Click here

    OK

  5. CHECK HARNESS AND CONNECTOR (FUEL PRESSURE SENSOR - ECM)


    1. Disconnect the fuel pressure 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
      C99-2 (PCR1) - C84-101 (PC) Always Below 1 Ω
      C99-3 (VC1) - C84-54 (VCS) Always Below 1 Ω
      C99-1 (E1) - C84-102 (E2S) Always Below 1 Ω
      C99-2 (PCR1) or C84-101 (PC) - Body ground Always 10 kΩ or higher
      C99-3 (VC1) or C84-54 (VCS) - Body ground Always 10 kΩ or higher
      C99-1 (E1) or C84-102 (E2S) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR Click here

    OK

  6. CHECK HARNESS AND CONNECTOR (VC VOLTAGE)


    1. Disconnect the fuel pressure 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
      C99-3 (VC1) - C99-1 (E1) Ignition switch ON 4.5 to 5.5 V

    NG

    REPLACE ECM Click here

    OK

  7. REPLACE DIESEL THROTTLE BODY ASSEMBLY


    1. Replace diesel throttle body assembly Click here.


    NEXT

  8. CHECK WHETHER DTC OUTPUT RECURS (DTC P0651)


    1. Connect the GTS to the DLC3.

    2. Turn the ignition switch to ON and turn the GTS on.

    3. Clear the DTCs Click here.

    4. Turn the ignition switch off and wait for 60 seconds or more [A].

    5. Turn the ignition switch to ON and wait for 15 seconds or more [B].

    6. Repeat [A] and [B] for the number of trips detected.

    7. Enter the following menus: Engine and ECT / Trouble Codes.

    8. Read the DTC.

      Result
      Result Proceed to
      No DTC output A
      DTC P0651 B

    B

    REPLACE ACCELERATOR PEDAL SENSOR ASSEMBLY Click here

    A

    END

  9. REPLACE ACCELERATOR PEDAL SENSOR ASSEMBLY


    1. Replace the accelerator pedal sensor assembly Click here.


    NEXT

  10. CHECK WHETHER DTC OUTPUT RECURS (DTC P0651)


    1. Connect the GTS to the DLC3.

    2. Turn the ignition switch to ON and turn the GTS on.

    3. Clear the DTCs Click here.

    4. Turn the ignition switch off and wait for 60 seconds or more [A].

    5. Turn the ignition switch to ON and wait for 15 seconds or more [B].

    6. Repeat [A] and [B] for the number of trips detected.

    7. Enter the following menus: Engine and ECT / Trouble Codes.

    8. Read the DTC.

      Result
      Result Proceed to
      No DTC output A
      DTC P0651 B

    B

    REPLACE FUEL PRESSURE SENSOR Click here

    A

    END

  11. REPLACE FUEL PRESSURE SENSOR


    1. Replace the fuel pressure sensor Click here.


    NEXT

    CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED Click here

  12. REPAIR OR REPLACE HARNESS OR CONNECTOR


    1. Repair or replace the harness or connector.


    NEXT

    CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED Click here

  13. REPLACE ECM


    1. Replace the ECM Click here.


    NEXT

  14. CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED


    1. Connect the GTS to the DLC3.

    2. Turn the ignition switch to ON and turn the GTS on.

    3. Clear the DTCs Click here.

    4. Turn the ignition switch off and wait for 60 seconds or more [A].

    5. Turn the ignition switch to ON and wait for 15 seconds or more [B].

    6. Repeat [A] and [B] for the number of trips detected.

    7. Enter the following menus: Engine and ECT / Trouble Codes.

    8. Confirm that the DTC is not output again.


    NEXT

    END