HYBRID CONTROL SYSTEM, Diagnostic DTC:P0A78-279

DTC Code DTC Name
P0A78-279 Drive Motor "A" Inverter Performance

DESCRIPTION

For a description of the inverter Click here.

If an overvoltage occurs in the motor inverter or generator inverter, the MG ECU detects it and transmits this information to the power management control ECU.

DTC No. INF Code DTC Detection Condition Trouble Area
P0A78 279 Motor inverter overvoltage signal detection (overvoltage (inverter malfunction)) Inverter with converter assembly

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 of 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 Click here.

Tech Tips

After the repair, clear the DTCs and perform the following procedure to check that DTCs are not output.


  1. With the vehicle engine stopped, the power switch on (READY) and park (P) selected, depress the accelerator pedal to start the engine.

PROCEDURE


  1. CHECK DTC OUTPUT (HYBRID CONTROL)


    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. Check if DTCs are output.

      Result
      Result Proceed to
      P0A78-279 is set before any of the DTCs in the table below are set. A
      Any of the DTCs including pending DTCs in the table 1 below are set before P0A78-279 is set. B
      DTC including pending DTC in the table 2 below is set before P0A78-279 is set. C
      Table 1
      DTC No. Relevant Diagnosis
      P3004-131, 803 High Voltage Power Resource
      Table 2
      DTC No. Relevant Diagnosis
      P31AB-123 Hybrid Battery Cell Low Voltage

      Tech Tips


      • Refer to the freeze frame data to determine the order in which the DTCs were set.

      • P0A78-279 may be set due to a malfunction which also causes DTCs in the preceding table to be set. In this case, first troubleshoot the output DTCs in the preceding table. Then, perform a test to attempt to reproduce the problems, and check that no DTCs are output.

    5. Turn the power switch off.


    B

    GO TO DTC CHART (HYBRID CONTROL SYSTEM) Click here

    C

    GO TO DTC CHART (P31AB-123) Click here

    A

  2. CHECK DTC OUTPUT (HYBRID CONTROL)


    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. Check if DTCs are output.

      Result
      Result Proceed to
      Only P0A78-279 is output, or DTCs other than the ones in the table below are also output. A
      Any of the following DTCs including pending DTCs in the table below are also output. B
      DTC No. Relevant Diagnosis
      P06B0-163 Sensor Power Supply "A" Circuit/Open
      P06D6-511 Sensor Reference Voltage "F" Circuit/Open
      P06E6-164 Sensor Power Supply "C" Circuit/Open
      P0A1A-151, 166, 517, 658, 791, 809 Generator Control Module
      P0A1B-198, 505, 554, 786, 794, 806 Drive Motor "A" Control Module
      P0A1D (all INF codes)*1 Hybrid Powertrain Control Module
      P0A3F-243 Drive Motor "A" Position Sensor Circuit
      P0A40-500, 506, 556, 808 Drive Motor "A" Position Sensor Circuit Range/Performance
      P0A41-245 Drive Motor "A" Position Sensor Circuit Low
      P0A4B-253 Generator Position Sensor Circuit
      P0A4C-513, 518, 811 Generator Position Sensor Circuit Range/Performance
      P0A4D-255 Generator Position Sensor Circuit Low
      P0A78-287, 555, 807 Drive Motor "A" Inverter Performance
      P0A7A-325, 810 Generator Inverter Performance
      P0A93-346 Inverter Cooling System Performance
      P0ADB-227 Hybrid Battery Positive Contactor Control Circuit Low
      P0ADC-226 Hybrid Battery Positive Contactor Control Circuit High
      P0ADF-229 Hybrid Battery Negative Contactor Control Circuit Low
      P0AE0-228 Hybrid Battery Negative Contactor Control Circuit High
      P0BEA-290 Drive Motor "A" Phase V Current Sensor Circuit Range/Performance
      P0BEE-298 Drive Motor "A" Phase W Current Sensor Circuit Range / Performance
      P0C73-776 Motor Electronics Coolant Pump "A" Control Performance
      P0C76-523 Hybrid battery System Discharge Time Too Long
      P0D2E-565, 586 Drive Motor "A" Inverter Voltage Sensor Circuit Range/Performance
      P0D2F-266 Drive Motor "A" Inverter Voltage Sensor Circuit Low
      P0D30-267 Drive Motor "A" Inverter Performance
      P0E05-328 Generator Phase V Current Sensor Circuit Range/Performance
      P0E09-336 Generator Phase W Current Sensor Circuit Range/Performance
      P0E32-585 DC/DC Converter Voltage Sensor "A" Range/Performance
      P0E33-589 DC/DC Converter Voltage Sensor "A" Low
      P0E34-590 DC/DC Converter Voltage Sensor "A" High
      P1C2A-155 Generator A/D Converter Circuit
      P1C2B-192 Drive Motor "A" A/D Converter Circuit
      P1C2D-587 Hybrid Battery Voltage / DC/DC Converter Voltage Correlation
      P1C3C-294 Drive Motor "A" Phase V Current Sensor Correlation
      P1C3D-302 Drive Motor "A" Phase W Current Sensor Correlation
      P1C3E-333 Generator Phase V Current Sensor Correlation
      P1C3F-341 Generator Phase W Current Sensor Correlation
      P1C4A-288 Drive Motor "A" Phase V Current Sensor Sub Circuit Range/Performance
      P1C4F-296 Drive Motor "A" Phase W Current Sensor Sub Circuit Range/Performance
      P1C54-326 Generator Phase V Current Sensor Sub Circuit Range/Performance
      P1C59-334 Generator Phase W Current Sensor Sub Circuit Range/Performance
      P1C6D-501 Drive Motor "A" Phase V Current Sensor Offset Range/Performance
      P1C6E-502 Drive Motor "A" Phase W Current Sensor Offset Range/Performance
      P1C71-515 Generator Phase V Current Sensor Offset Range/Performance
      P1C72-516 Generator Phase W Current Sensor Offset Range/Performance
      P1C73-512 Sensor Standard Voltage "F" Circuit/Open
      P1CA6-156 Generator Control Module Malfunction
      P1CA7-193 Drive Motor Control Module Malfunction
      P1CAC-200 Generator Position Sensor Angle Malfunction
      P1CAD-168 Drive Motor "A" Position Sensor Angle Malfunction
      P1CAF-792 Generator Position Sensor REF Signal Cycle Malfunction
      P1CB0-795 Drive Motor "A" Position Sensor REF Signal Cycle Malfunction
      P1CB2-793 Generator Position Sensor REF Signal Stop Malfunction
      P1CB3-796 Drive Motor "A" Position Sensor REF Signal Stop Malfunction
      P3004-803 Power Cable Malfunction
      P3133-659 Communication Error from Generator to Drive Motor "A"
      P3134-661 Communication Error from Drive Motor "A" to Generator
      P314A-828 Inverter Coolant Pump Speed Signal

      Tech Tips


      • *1: If any INF codes are output for this DTC, refer to the corresponding diagnostic procedure.

      • P0A78-279 may be set due to a malfunction which also causes DTCs in the preceding table to be set. In this case, first troubleshoot the output DTCs in the preceding table. Then, perform a test to attempt to reproduce the problems, and check that no DTCs are output.

    5. Turn the power switch off.


    B

    GO TO DTC CHART (HYBRID CONTROL SYSTEM) Click here

    A

  3. CHECK CONNECTOR CONNECTION CONDITION (INVERTER WITH CONVERTER ASSEMBLY CONNECTOR)

    CAUTION:

    Be sure to wear insulated gloves.


    1. A005CAR

      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.

      Note

      Before disconnecting the connector, confirm that it is properly connected by checking that the locking claws are engaged and that the connector does not pull out.

    2. Check the connection of the low voltage connector of the inverter with converter assembly.

      OK
      The connector is connected securely and there are no contact problems.

      Tech Tips

      When connecting the connector, insert it with the locking lever in the raised position. Rotate the lever downward and make sure that the connector is pulled into its socket. When the locking lever is in its fully closed position, a click will be heard as its locking claws engage. After the click is heard, pull up on the connector to confirm that it is properly connected.


    OK

    REFER TO REPLACE INVERTER WITH CONVERTER ASSEMBLY PARTS Click here

    NG

    CONNECT SECURELY