HYBRID CONTROL SYSTEM, Diagnostic DTC:P0C76-523

DTC Code DTC Name
P0C76-523 Hybrid Battery System Discharge Time Too Long

DESCRIPTION

For a description of the inverter Click here.

DTC No. DTC Detection Condition Trouble Area
P0C76-523

The inverter voltage (VH) does not drop during discharge.

(Discharge: Offsetting of the residual pressure in the high-voltage side after power switch is turned off)

(1 trip detection logic)

  • Inverter with converter assembly

  • Wire harness or connector

  • Power management control ECU

Tech Tips

When the power switch is turned from on (READY) to off, the MG ECU discharges voltage stored in the inverter by allowing current to flow to motor (MG2) without generating torque. When the vehicle is normal, VH voltage becomes approximately 0 V after discharging. If VH voltage exceeds a specified value, this DTC is stored.

A000PM9E02
Related Data List
DTC No. Data List
P0C76-523 VL-Voltage before Boosting

Use the following items as references when performing repairs.


WIRING DIAGRAM

Refer to the wiring diagram for DTC P0AE6-225 Click here.

Refer to the wiring diagram for DTC P321E-318 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 Click here.

Tech Tips

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


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

  2. Turn the power switch on (READY) and wait for 30 seconds or more.

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

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 for DTCs.

      Result
      Result Proceed to
      P0C76-523 only is output, or DTCs except the ones in the table below are also output. A
      Any of the following DTCs including pending DTCs 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, 658, 791 Generator Control Module
      P0A1B-786, 794 Drive Motor "A" Control Module
      P0A1D-148 Hybrid Powertrain Control Module
      P0A3F-243 Drive Motor "A" Position Sensor Circuit
      P0A40-500 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 Generator Position Sensor Circuit Range/Performance
      P0A4D-255 Generator Position Sensor Circuit Low
      P0ADC-226 Hybrid Battery Positive Contactor Control Circuit High
      P0AE0-228 Hybrid Battery Negative Contactor Control Circuit High
      P0AE7-224 Hybrid Battery Precharge Contactor Control Circuit High
      P0D2F-266 Drive Motor "A" Inverter Voltage Sensor Circuit Low
      P0D30-267 Drive Motor "A" Inverter Voltage Sensor Circuit High
      P1C2A-155 Generator A/D Converter Circuit
      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
      P2511-149 ECM/PCM Power Relay Sensor Circuit Intermittent
      P3133-659 Communication Error from Generator to Drive Motor "A"
      P3134-661 Communication Error from Drive Motor "A" to Generator
      P324E-788 MG-ECU Power Relay Intermittent Circuit
      U0110 (all INF codes)*1 Lost Communication with Drive Motor Control Module

      Tech Tips


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

      • P0C76-523 may be stored due to a malfunction which causes the DTCs in the preceding table to be stored. In this case, first troubleshoot the output DTCs in the preceding table. Then, perform a reproduction test to check that no DTCs are output.

    5. Turn the power switch off.


    B

    GO TO DTC CHART (HYBRID CONTROL SYSTEM) 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 for DTCs.

      Result
      Result Proceed to
      Any of the following DTCs are also output. A
      P0C76-523 only is output, or DTCs except the ones in the table below are also output. B
      DTC No. Relevant Diagnosis
      P0A90-251, 509 Drive Motor "A" Performance
      P0A92-261, 521 Hybrid Generator Performance
      P0C19-306 Drive Motor "A" Torque Delivered Performance
      P0E71-344 Generator Torque Delivered Performance

      Tech Tips

      When the DTCs listed in the preceding table are also output, there may be a short between the HSDN (MG shut down signal) circuit and power circuit.

    5. Turn the power switch off.


    B

    REPLACE INVERTER WITH CONVERTER ASSEMBLY Click here

    A

  3. CHECK POWER MANAGEMENT CONTROL ECU


    1. Turn the power switch on (IG).

    2. A000NU0E02
      Text in Illustration
      *a

      Component with harness connected

      (Power Management Control ECU)

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

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      A35-30 (HSDN) - N91-6 (E1) Power switch on (IG) Below 4.5 V

    3. Turn the power switch off.


    OK

    REPLACE INVERTER WITH CONVERTER ASSEMBLY Click here

    NG

  4. CHECK HARNESS AND CONNECTOR (POWER MANAGEMENT CONTROL ECU - INVERTER WITH CONVERTER 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 A35 power management control ECU connector.

    3. Disconnect the A38*1 or A74*2 inverter with converter assembly connector


      • *1: for LHD

      • *2: for RHD

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

    5. Turn the power switch on (IG).

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

      A000NZHE02
      Text in Illustration
      *A for LHD *B for RHD
      *a

      Rear view of wire harness connector

      (to Power Management Control ECU)

      		 *b

      Front view of wire harness connector

      (to Inverter with Converter Assembly)
      Standard Voltage
      for LHD
      Tester Connection Switch Condition Specified Condition
      A35-30 (HSDN) or A38-25 (HSDN) - Body ground Power switch on (IG) Below 1 V
      for RHD
      Tester Connection Switch Condition Specified Condition
      A74-30 (HSDN) or A74-25 (HSDN) - Body ground Power switch on (IG) Below 1 V

      Note

      Turning the power switch on (IG) with the power management control ECU and inverter with converter assembly connector 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. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      for LHD
      Tester Connection Switch Condition Specified Condition
      A35-30 (HSDN) - A35-1 (+B2) Power switch off 10 kΩ or higher
      A35-30 (HSDN) - A35-4 (MREL) Power switch off 10 kΩ or higher
      A38-25 (HSDN) - A38-10 (+B) Power switch off 10 kΩ or higher
      A38-25 (HSDN) - A38-11 (+B2) Power switch off 10 kΩ or higher
      for RHD
      Tester Connection Switch Condition Specified Condition
      A35-30 (HSDN) - A35-1 (+B2) Power switch off 10 kΩ or higher
      A35-30 (HSDN) - A35-4 (MREL) Power switch off 10 kΩ or higher
      A74-25 (HSDN) - A74-10 (+B) Power switch off 10 kΩ or higher
      A74-25 (HSDN) - A74-11 (+B2) Power switch off 10 kΩ or higher

    10. Reconnect the A38*1 or A74*2 inverter with converter assembly connector.


      • *1: for LHD

      • *2: for RHD

    11. Reconnect the A35 power management control ECU connector.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  5. CHECK INVERTER WITH CONVERTER 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 A38*1 or A74*2 inverter with converter assembly connector.


      • *1: for LHD

      • *2: for RHD

    3. A000RTME01
      Text in Illustration
      *A for LHD
      *B for RHD
      *a

      Component without harness connected

      (Inverter with Converter Assembly)

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

      Standard Resistance
      for LHD
      Tester Connection Switch Condition Specified Condition
      A38-25 (HSDN) - A38-10 (+B) Power switch off 5 kΩ or higher
      A38-25 (HSDN) - A38-11 (+B2) Power switch off 5 kΩ or higher
      for RHD
      Tester Connection Switch Condition Specified Condition
      A74-25 (HSDN) - A74-10 (+B) Power switch off 5 kΩ or higher
      A74-25 (HSDN) - A74-11 (+B2) Power switch off 5 kΩ or higher

    4. Reconnect the A38*1 or A74*2 inverter with converter assembly connector


      • *1: for LHD

      • *2: for RHD


    OK

    REPLACE POWER MANAGEMENT CONTROL ECU Click here

    NG

    REPLACE INVERTER WITH CONVERTER ASSEMBLY Click here