HYBRID CONTROL SYSTEM, Diagnostic DTC:P1C8449

DTC Code DTC Name
P1C8449 High Voltage Power Resource Circuit Short during Ready ON

DTC SUMMARY


  1. MALFUNCTION DESCRIPTION

    The hybrid vehicle control ECU monitors the high-voltage wiring between the HV battery and inverter with converter assembly and detects an open circuit malfunction.

    Tech Tips


    • This DTC is differentiated from P300449 based on detection timing (after power switch is turned on (READY)). If P300449 is also output at the same time, first perform troubleshooting for P300449.

    • If there is a SMRG stuck open malfunction, only P1C8449 is output.

    The cause of this malfunction may be one of the following:


      Inverter voltage sensor (VH or VL) internal circuit malfunction

    • Voltage sensor (VH or VL) malfunction

    • Motor generator control ECU (MG ECU) malfunction

    • Communication (wire harness) malfunction


      High voltage system malfunction

    • HV battery malfunction

    • HV battery junction block assembly malfunction

    • Inverter with converter assembly malfunction

    • High-voltage wire harness malfunction

    • High-voltage connector or connection malfunction


      Low-voltage circuit (12 V) malfunction

    • Hybrid vehicle control ECU malfunction

    • HV battery junction block assembly malfunction

    • Low voltage wire harness malfunction

    • Low voltage connector malfunction

DESCRIPTION

Refer to the description for DTC P0AE411.

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DTC No. Detection Item DTC Detection Condition Trouble Area MIL Warning Indicate
P1C8449 High Voltage Power Resource Circuit Short during Ready ON

High-voltage circuit malfunctions between the HV battery and inverter with converter assembly.

When the power switch is on (READY), both "VL-Voltage before Boosting" and "VH-Voltage after Boosting" drop abnormally.

The EV electric battery fuse is blown, the service plug grip is removed, SMRB or SMRG remains open, or the high-voltage cable has an open circuit.

(1 trip detection logic)

  • HV battery junction block assembly

  • Wire harness or connector

  • Hybrid vehicle control ECU

 Does not come on

Master Warning Light:

Comes on
Related Data List
DTC No. Data List
P1C8449

  • Hybrid Battery Voltage

  • Hybrid Battery Current

  • VL-Voltage before Boosting

  • VH-Voltage after Boosting

The following items can be helpful when performing repairs:


CONFIRMATION DRIVING PATTERN

Tech Tips

After repairs have been completed, clear the DTCs and then check that the vehicle has returned to normal by performing the following All Readiness check procedure.

Click here


  1. Connect the GTS to the DLC3.

  2. Turn the power 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 power switch off and wait for 2 minutes or more.

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

  6. Turn the power switch on (READY) and wait for 3 minutes or more.

    Tech Tips

    According to the display on the GTS, read the Data List and monitor the values of "Hybrid Battery Voltage" and "VL-Voltage before Boosting" for 3 minutes. If the difference between "Hybrid Battery Voltage" and "VL-Voltage before Boosting" is always less than 50 V, the vehicle has returned to normal.

  7. Enter the following menus: Powertrain / Hybrid Control / Utility / All Readiness.

  8. Check the DTC judgment result.

    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, perform driving pattern again.

WIRING DIAGRAM

Refer to the wiring diagram for the HV battery high-voltage line circuit.

Click here

CAUTION / NOTICE / HINT

CAUTION:


  • Before inspecting the high-voltage system or disconnecting the low voltage connector of the inverter with converter assembly, take safety precautions such as wearing insulated gloves and removing the service plug grip to prevent electrical shocks. After removing the service plug grip, put it in your pocket to prevent other technicians from accidentally reconnecting it while you are working on the high-voltage system.

  • After removing the service plug grip, wait for at least 10 minutes before touching any of the high-voltage connectors or terminals. After waiting for 10 minutes, check the voltage at the terminals in the inspection point in the inverter with converter assembly. The voltage should be 0 V before beginning work.

    Click here

    Tech Tips

    Waiting for at least 10 minutes is required to discharge the high-voltage capacitor inside the inverter with converter assembly.

Note

After turning the power switch off, waiting time may be required before disconnecting the cable from the negative (-) auxiliary battery terminal. Therefore, make sure to read the disconnecting the cable from the negative (-) auxiliary battery terminal notices before proceeding with work.

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PROCEDURE


  1. CHECK DTC OUTPUT (HYBRID CONTROL, MOTOR GENERATOR)


    1. Connect the GTS to the DLC3.

    2. Turn the power switch on (IG).

    3. Enter the following menus: Powertrain / Hybrid Control and Motor Generator / Trouble Codes.

    4. Check for DTCs.


      Powertrain > Hybrid Control > Trouble Codes
      Powertrain > Motor Generator > Trouble Codes
      Result
      Result Proceed to
      P1C8449 only is output, or P0A9563 and DTCs except the ones in the table below are also output. A
      DTCs of hybrid control system in the tables below are output. B
      DTCs of motor generator control system in the tables below are output. C
      P0A9563 is also output. D
      Malfunction Content System Relevant DTC
      Microcomputer malfunction Hybrid control system P0A1B49 Drive Motor "A" Control Module Internal Electronic Failure
      P060647 Hybrid/EV Powertrain Control Module Processor Watchdog / Safety MCU Failure
      Motor generator control system P0A1B1F Generator Control Module Circuit Intermittent
      P0A1A47 Generator Control Module Watchdog / Safety μC Failure
      P0A1A49 Generator Control Module Internal Electronic Failure
      P1C2A1C Generator A/D Converter Circuit Circuit Voltage Out of Range
      P1C2A49 Generator A/D Converter Circuit Internal Electronic Failure
      P313383 Communication Error from Generator to Drive Motor "A" Value of Signal Protection Calculation Incorrect
      P313386 Communication Error from Generator to Drive Motor "A" Signal Invalid
      P313387 Communication Error from Generator to Drive Motor "A" Missing Message
      Power source circuit malfunction Motor generator control system P06D61C Generator Control Module Offset Power Circuit Voltage Out of Range
      Communication system malfunction Hybrid control system P312387 Lost Communication with Drive Motor Control Module "A" from Hybrid/EV Control Module Missing Message
      System malfunction Hybrid control system P0C7600 Hybrid/EV Battery System Discharge Time Too Long
      P0D2D1C Drive Motor "A" Inverter Voltage Sensor Voltage Out of Range
      P1C8349 High Voltage Power Resource Circuit Voltage Sensor after Boosting Malfunction
      P0E311C Boosting Converter Voltage Sensor "A" Voltage Out of Range
      Motor generator control system P0D2D16 Drive Motor "A" Inverter Voltage Sensor(VH) Circuit Voltage Below Threshold
      P0D2D17 Drive Motor "A" Inverter Voltage Sensor(VH) Circuit Voltage Above Threshold
      P1CB69E Drive Motor "A" Inverter Voltage Sensor(VH) Stuck On
      P0CA300 DC/DC Converter Step Up Voltage Performance

      Tech Tips


      • P1C8449 may be output as a result of the malfunction indicated by the DTCs above.


        1. The chart above is listed in inspection order of priority.

        2. Check DTCs that are output at the same time by following the listed order. (The main cause of the malfunction can be determined without performing unnecessary inspections.)

    5. Turn the power switch off.


    B

    GO TO DTC CHART (HYBRID CONTROL SYSTEM) Click here

    C

    GO TO DTC CHART (MOTOR GENERATOR CONTROL SYSTEM) Click here

    D

    GO TO DTC CHART (P0A9563) Click here

    A

  2. CLEAR DTC


    1. Connect the GTS to the DLC3.

    2. Turn the power switch on (IG).

    3. Enter the following menus: Powertrain / Hybrid Control / Trouble Codes.

    4. Clear the DTCs.


      Powertrain > Hybrid Control > Clear DTCs

    5. Turn the power switch off.

      Result
      Proceed to
      NEXT

    NEXT

  3. CHECK DTC OUTPUT (HYBRID CONTROL)


    1. Connect the GTS to the DLC3.

    2. With the vehicle stopped, apply the parking brake and turn the power switch on (READY).

      Tech Tips


      • If the power switch could not be turned on (READY), turn the power switch off and check for DTCs after turning the power switch on (READY) again.

      • Because P300449 uses 2 trip detection logic, the DTC detection conditions need to be met 2 times.

    3. Ensure the safety of the areas in front and at the back of the vehicle.

    4. Move the shift lever to D and depress both the accelerator pedal and brake pedal at the same time.

      Tech Tips

      Depressing both the accelerator pedal and brake pedal at the same time causes the HV battery current to flow and ensures that there is no problem with the high-voltage wiring.

    5. Enter the following menus: Powertrain / Hybrid Control / Trouble Codes.


      Powertrain > Hybrid Control > Trouble Codes

    6. Check for DTCs.

      Result
      Result Proceed to
      P1C8449 is output, or no DTCs are output. A
      Power switch could not be turned on (READY) and DTC P300449 is output. B

    7. Turn the power switch off.


    B

    GO TO DTC CHART (P300449) Click here

    A

  4. CHECK CONNECTOR CONNECTION CONDITION (HYBRID VEHICLE CONTROL ECU CONNECTOR)


    1. Check the connector connections and contact pressure of the relevant terminals for the hybrid vehicle control ECU connectors.

      Tech Tips

      Click here

      B004P9FC01
      *A for LHD *B for RHD
      OK
      The connectors are connected securely and there are no contact pressure problems.
      Result
      Proceed to
      OK
      NG

    NG

    CONNECT SECURELY

    OK

  5. CHECK CONNECTOR CONNECTION CONDITION (FLOOR WIRE CONNECTOR)


    1. B004OUBC01
      *A for LHD
      *B for RHD

      Check the connection condition of the MF2 or MF1 floor wire connector and the contact pressure of each terminal. Check the terminals for deformation, and check the connector for water ingress and foreign matter.

      Tech Tips

      Click here

      OK
      - The connector is connected securely.
      - The terminals are not deformed and are connected securely.
      - No water or foreign matter in the connector.
      Result
      Result Proceed to
      OK A
      NG (The connector is not connected securely.) B
      NG (The terminals are not making secure contact or are deformed, or water or foreign matter exists in the connector.) C

    B

    CONNECT SECURELY

    C

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    A

  6. CHECK CONNECTOR CONNECTION CONDITION (HV BATTERY JUNCTION BLOCK ASSEMBLY CONNECTOR)

    CAUTION:

    Be sure to wear insulated gloves.


    1. Check that the service plug grip is not installed.

      Note

      After removing the service plug grip, do not turn the power switch on (READY), unless instructed by the repair manual because this may cause a malfunction.

    2. Remove the No. 1 HV battery cover panel RH.

      Tech Tips

      Click here

    3. B004PQ3N02

      Check the connector connections and contact pressure of the relevant terminals of the M37 HV battery junction block assembly connector.

      Tech Tips

      Click here

      OK
      The connectors are connected securely and there are no contact pressure problems.

    4. Install the No. 1 HV battery cover panel RH.

      Result
      Proceed to
      OK
      NG

    NG

    CONNECT SECURELY

    OK

  7. CHECK HARNESS AND CONNECTOR (HYBRID VEHICLE CONTROL ECU - HV BATTERY JUNCTION BLOCK ASSEMBLY)

    CAUTION:

    Be sure to wear insulated gloves.


    1. Check that the service plug grip is not installed.

      Note

      After removing the service plug grip, do not turn the power switch on (READY), unless instructed by the repair manual because this may cause a malfunction.

    2. Remove the No. 1 HV battery cover panel RH.

      Tech Tips

      Click here

    3. Disconnect the M37 HV battery junction block assembly connector.

    4. Disconnect the F2 hybrid vehicle control ECU connector.

    5. B004OMTC20
      *a

      Front view of wire harness connector

      (to Hybrid Vehicle Control ECU)
      *b

      Front view of wire harness connector

      (to HV Battery Junction Block Assembly)

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      F2-16 (SMRB) - M37-1 (SMRB) Power switch off Below 1 Ω
      F2-13 (SMRG) - M37-4 (SMRG) Power switch off Below 1 Ω

    6. Reconnect the F2 hybrid vehicle control ECU connector.

    7. Reconnect the M37 HV battery junction block assembly connector.

    8. Install the No. 1 HV battery cover panel RH.

      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  8. CHECK HARNESS AND CONNECTOR (HV BATTERY JUNCTION BLOCK ASSEMBLY - BODY GROUND)

    CAUTION:

    Be sure to wear insulated gloves.


    1. Check that the service plug grip is not installed.

      Note

      After removing the service plug grip, do not turn the power switch on (READY), unless instructed by the repair manual because this may cause a malfunction.

    2. Remove the No. 1 HV battery cover panel RH.

      Tech Tips

      Click here

    3. Disconnect the M37 HV battery junction block assembly connector.

    4. B004QCIC04
      *a

      Front view of wire harness connector

      (to HV Battery Junction Block Assembly)

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      M37-3 (GND) - Body ground Power switch off Below 1 Ω

    5. Reconnect the M37 HV battery junction block assembly connector.

    6. Install the No. 1 HV battery cover panel RH.

      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  9. REPLACE HV BATTERY JUNCTION BLOCK ASSEMBLY

    Tech Tips

    Click here

    Result
    Proceed to
    NEXT

    NEXT

  10. CHECK HYBRID VEHICLE CONTROL ECU (CHECK FOR NORMAL OPERATION)


    1. Install the service plug grip.

    2. Turn the power switch on (IG).

    3. Clear the DTCs.


      Powertrain > Hybrid Control > Clear DTCs

    4. Turn the power switch off and wait for 30 seconds or more.

    5. Turn the power switch on (READY).

    6. Enter the following menus: Powertrain / Hybrid Control / Data List / Hybrid Battery Voltage, VL-Voltage before Boosting.

    7. According to the display on the GTS, read the Data List and monitor the values of "Hybrid Battery Voltage" and "VL-Voltage before Boosting" for 3 minutes.


      Powertrain > Hybrid Control > Data List
      Tester Display
      VL-Voltage before Boosting
      Hybrid Battery Voltage
      Result
      Result Proceed to
      Difference between "Hybrid Battery Voltage" and "VL-Voltage before Boosting" is always less than 50 V. A
      Difference between "Hybrid Battery Voltage" and "VL-Voltage before Boosting" is 50 V or more. B

    8. Turn the power switch off.


    A

    END

    B

    REPLACE HYBRID VEHICLE CONTROL ECU Click here