HYBRID CONTROL SYSTEM, Diagnostic DTC:P312387

DTC Code DTC Name
P312387 Lost Communication with Drive Motor Control Module "A" from Hybrid/EV Control Module Missing Message

DESCRIPTION

For a description of the inverter.

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The MG ECU, which is built into in the inverter with converter assembly, controls motor (MG2) based on commands from the hybrid vehicle control ECU assembly. The MG ECU monitors communication data and detects malfunctions.

The hybrid vehicle control ECU assembly monitors communication data and detects malfunctions.

A communication error between the MG ECU and the hybrid vehicle control ECU assembly.

DTC No. Detection Item DTC Detection Condition Trouble Area MIL Warning Indicate
P312387 Lost Communication with Drive Motor Control Module "A" from Hybrid/EV Control Module Missing Message

Error in reception from inverter with converter assembly (MG ECU) via serial communication (out of communication standard)

(1 trip detection logic)

  • Wire harness or connector

  • Inverter with converter assembly

  • Hybrid vehicle transmission assembly

  • Hybrid vehicle control ECU assembly

  • IGCT NO.2 fuse

 Come on

Master Warning Light:

Comes on

CONFIRMATION DRIVING PATTERN

Tech Tips

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

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  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. With power switch on (IG) and wait for 2 minutes or more.

  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 inverter low-voltage circuit.

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CAUTION / NOTICE / HINT

CAUTION:


  • B004BJX

    Before the following operations are conducted, take precautions to prevent electric shock by turning the power switch off, wearing insulated gloves, and removing the service plug grip from HV battery.


    • Inspecting the high-voltage system

    • Disconnecting the low voltage connector of the inverter with converter assembly

    • Disconnecting the low voltage connector of the HV battery

  • B004C5R

    To prevent electric shock, make sure to remove the service plug grip to cut off the high voltage circuit before servicing the vehicle.

  • B0049VM

    After removing the service plug grip from the HV battery, put it in your pocket to prevent other technicians from accidentally reconnecting it while you are working on the high-voltage system.

  • B004AZGC06
    *a Without waiting for 10 minutes

    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. INSPECT FUSE (IGCT NO.2)


    1. Remove the IGCT NO.2 fuse from the No. 2 Luggage Room Relay Block.

    2. B004A3NC02
      *1 No. 2 Luggage Room Relay Block
      *2 IGCT NO.2 Fuse

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      IGCT NO.2 fuse terminals Always Below 1 Ω

    3. Install the IGCT NO.2 fuse.

      Result
      Proceed to
      OK
      NG

    NG

    REPLACE FUSE (IGCT NO.2) Click here

    OK

  2. CLEAR DTC

    Result
    Proceed to
    NEXT

    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. Read and record the DTCs and freeze frame data.


      Powertrain > Hybrid Control > Trouble Codes

    5. Clear the DTCs and freeze frame data.


      Powertrain > Hybrid Control > Clear DTCs

    6. Turn the power switch off.

      Result
      Proceed to
      NEXT

    NEXT

  3. CHECK DIAGNOSIS RELATED INFORMATION AND DTC OUTPUT (HYBRID CONTROL)


    1. Connect the GTS to the DLC3.

    2. Turn the power switch on (IG) and wait for 2 minutes or more.

    3. Enter the following menus: Powertrain / Hybrid Control / Utility / Diagnosis Related Information.


      Powertrain > Hybrid Control > Utility
      Tester Display
      Diagnosis Related Information

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


      Powertrain > Hybrid Control > Trouble Codes

    5. Check for DTCs.

      Result
      Result Proceed to
      P312387 is listed in Diagnosis Related Information or DTC P312387 is output. A
      P312387 is not listed in Diagnosis Information and DTC P312387 is not output. B

    6. Turn the power switch off.


    B

    CHECK FOR INTERMITTENT PROBLEMS Click here

    A

  4. CHECK HARNESS AND CONNECTOR (INVERTER WITH CONVERTER ASSEMBLY POWER SOURCE CIRCUIT)

    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. Disconnect the A23*1 or A24*2 inverter with converter assembly connector.

      Click here


      • *1: for LHD

      • *2: for RHD

    3. B004A2EC20
      *A for LHD
      *B for LHD
      *a

      Front view of wire harness connector

      (to Inverter with Converter Assembly)

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

      Standard Resistance
      for LHD
      Tester Connection Condition Specified Condition
      A23-30 (GND1) - Body ground Power switch off Below 1 Ω
      A23-31 (GND2) - Body ground Power switch off Below 1 Ω
      for RHD
      Tester Connection Condition Specified Condition
      A24-30 (GND1) - Body ground Power switch off Below 1 Ω
      A24-31 (GND2) - Body ground Power switch off Below 1 Ω

    4. Connect the cable to the negative (-) auxiliary battery terminal and wait for 2 minutes or more.

    5. Turn the power switch on (IG).

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

      Standard Voltage
      for LHD
      Tester Connection Condition Specified Condition
      A23-10 (+B) - Body ground Power switch on (IG) 11 to 14 V
      A23-11 (+B2) - Body ground Power switch on (IG) 11 to 14 V
      for RHD
      Tester Connection Condition Specified Condition
      A24-10 (+B) - Body ground Power switch on (IG) 11 to 14 V
      A24-11 (+B2) - Body ground Power switch on (IG) 11 to 14 V

      Note

      Turning the power switch on (IG) with the inverter with converter assembly disconnected causes other DTCs to be stored. Clear the DTCs after performing this inspection.

    7. Turn the power switch off.

    8. Disconnect the cable from the negative (-) auxiliary battery terminal.

    9. Reconnect the A23*1 or A24*2 inverter with converter assembly connector.


      • *1: for LHD

      • *2: for RHD

      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  5. CHECK HARNESS AND CONNECTOR (INVERTER WITH CONVERTER ASSEMBLY - HYBRID VEHICLE CONTROL ECU 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. Disconnect the A23*1 or A24*2 inverter with converter assembly connector.


      • *1: for LHD

      • *2: for RHD

    3. Disconnect the A22 hybrid vehicle control ECU assembly connector.

    4. Connect the cable to the negative (-) auxiliary battery terminal.

    5. Turn the power switch on (IG).

    6. B004BIEC12
      *A for LHD
      *B for RHD
      *a

      Front view of wire harness connector

      (to Inverter with Converter Assembly)
      *b

      Rear view of wire harness connector

      (to Hybrid Vehicle Control ECU Assembly)

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      A22-20 (HMCL) - Body ground Power switch on (IG) Below 1 V
      A22-28 (HMCH) - Body ground Power switch on (IG) Below 1 V

      Note

      Turning the power switch on (IG) with the hybrid vehicle control ECU assembly connector and the inverter with converter assembly disconnected causes other DTCs to be stored. Clear the DTCs after performing this inspection.

    7. Turn the power switch off.

    8. Disconnect the cable from the negative (-) auxiliary battery terminal and wait for 2 minutes or more.

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

      Standard Resistance (Check for Open)
      for LHD
      Tester Connection Condition Specified Condition
      A23-6 (HMCL) - A22-20 (HMCL) Power switch off Below 1 Ω
      A23-5 (HMCH) - A22-28 (HMCH) Power switch off Below 1 Ω
      for RHD
      Tester Connection Condition Specified Condition
      A24-6 (HMCL) - A22-20 (HMCL) Power switch off Below 1 Ω
      A24-5 (HMCH) - A22-28 (HMCH) Power switch off Below 1 Ω
      Standard Resistance (Check for Short)
      for LHD
      Tester Connection Condition Specified Condition
      A23-6 (HMCL) or A22-20 (HMCL) - Body ground and other terminals Power switch off 10 kΩ or higher
      A23-5 (HMCH) or A22-28 (HMCH) - Body ground and other terminals Power switch off 10 kΩ or higher
      for RHD
      Tester Connection Condition Specified Condition
      A24-6 (HMCL) or A22-20 (HMCL) - Body ground and other terminals Power switch off 10 kΩ or higher
      A24-5 (HMCH) or A22-28 (HMCH) - Body ground and other terminals Power switch off 10 kΩ or higher

    10. Reconnect the A22 hybrid vehicle control ECU assembly connector.

    11. Reconnect the A23*1 or A24*2 inverter with converter assembly connector.


      • *1: for LHD

      • *2: for RHD

      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  6. CHECK INVERTER WITH CONVERTER ASSEMBLY (INTERNAL RESISTANCE)

    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. Disconnect the A23*1 or A24*2 inverter with converter assembly connector.


      • *1: for LHD

      • *2: for RHD

    3. B004A95C90
      *a

      Component with harness connected

      (Hybrid Vehicle Control ECU Assembly)

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A22-20 (HMCL) -A22-28 (HMCH) Power switch off 110 to 130 Ω

    4. Reconnect the A23*1 or A24*2 inverter with converter assembly connector.


      • *1: for LHD

      • *2: for RHD

      Result
      Proceed to
      OK
      NG

    OK

    REPLACE INVERTER WITH CONVERTER ASSEMBLY Click here

    NG

    REPLACE HYBRID VEHICLE CONTROL ECU ASSEMBLY Click here

  7. REPLACE FUSE (IGCT NO.2)


    1. B004A3NC02
      *1 No. 2 Luggage Room Relay Block
      *2 IGCT NO.2 Fuse

      Replace the IGCT NO.2 fuse.

    2. Turn the power switch on (READY).

    3. Check if there is an open circuit in the IGCT NO.2 fuse in the No. 2 luggage room relay block.

      OK
      There is no open circuit in the IGCT NO.2 fuse.

      Tech Tips

      If the fuse does not become open again after turning the power switch on (READY), it can be assumed that the previous fuse failed due to age.

    4. Turn the power switch off.

      Result
      Proceed to
      OK
      NG

    OK

    COMPLETED

    NG

  8. CHECK HARNESS AND CONNECTOR (INVERTER WITH CONVERTER ASSEMBLY - NO. 2 LUGGAGE ROOM RELAY BLOCK)

    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 IGCT NO.2 fuse from the No. 2 luggage room relay block.

    3. Disconnect the A23*1 or A24*2 inverter with converter assembly connector.


      • *1: for LHD

      • *2: for RHD

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

      B004BZ8C03
      *A for LHD *B for RHD
      *1 No. 2 Luggage Room Relay Block *2 IGCT NO.2 Fuse
      *a

      Front view of wire harness connector

      (to Inverter with Converter Assembly)

      		 - -
      Standard Resistance (Check for Short)
      for LHD
      Tester Connection Condition Specified Condition
      A23-10 (+B), A23-11 (+B2) or 2 (IGCT NO.2 fuse terminal) - Body ground and other terminals Power switch off 10 kΩ or higher
      for RHD
      Tester Connection Condition Specified Condition
      A24-10 (+B), A24-11 (+B2) or 2 (IGCT NO.2 fuse terminal) - Body ground and other terminals Power switch off 10 kΩ or higher

    5. Reconnect the A23*1 or A24*2 inverter with converter assembly connector.


      • *1: for LHD

      • *2: for RHD

    6. Install the IGCT NO.2 fuse.

      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR Click here

    OK

  9. REPLACE INVERTER WITH CONVERTER ASSEMBLY

    Click here

    Result
    Proceed to
    NEXT

    NEXT

    REPLACE FUSE (PCU FR)

  10. REPAIR OR REPLACE HARNESS OR CONNECTOR

    Result
    Proceed to
    NEXT

    NEXT

    REPLACE FUSE (PCU FR)