HYBRID CONTROL SYSTEM, Diagnostic DTC:P0C76-523

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

DTC SUMMARY

MALFUNCTION DESCRIPTION

The power management control ECU detects that the electrical charge stored in the high-voltage condenser of the inverter with converter assembly cannot be discharged.

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


  1. Inside of inverter voltage sensor (VH) circuit malfunction


    • Voltage sensor (VH) malfunction

    • Motor generator control ECU (MG ECU) malfunction

    • Communication (wire harness) malfunction

  2. High voltage system malfunction


    • Inverter with converter assembly malfunction

  3. Shutdown signal circuit malfunction


    • Power management control ECU malfunction

    • Wire harness malfunction

    • Inverter with converter assembly malfunction

DESCRIPTION

Refer to the description for DTC P0A78-266 Click here.

DTC No. INF Code 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.

A01I473E02
Related Data List
DTC No. Data List
P0C76-523 VL-Voltage before Boosting

The following items can be helpful when performing repairs:

Data List


WIRING DIAGRAM

Refer to the wiring diagram for the shut down signal circuit Click here.

INSPECTION PROCEDURE

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 Techstream 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
      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
      Malfunction Content Relevant DTC
      Microcomputer malfunction P0A1A-151, 155, 156, 200, 658, 659, 791, 792, 793 Generator Control Module
      P0A1B-163, 164, 168, 193, 511, 512, 661, 786, 794, 795, 796 Drive Motor "A" Control Module
      P0A1D-148 Hybrid Powertrain Control Module
      P324E-788 MG-ECU Power Relay Intermittent Circuit
      Power source circuit malfunction P2511-149 ECM/PCM Power Relay Sensor Circuit Intermittent
      Communication system malfunction U0110 (all INF codes)*1 Lost Communication with Drive Motor Control Module "A"
      Sensor and actuator circuit malfunction 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
      P0A78-266, 267 Drive Motor "A" Inverter Performance
      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

      Tech Tips


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

      • P0C76-523 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

    A

  2. CHECK SHUT DOWN SIGNAL CIRCUIT

    Click here

    Tech Tips

    If the "Shut Down Signal Circuit" inspection results are normal, perform the next step.


    NEXT

    REPLACE INVERTER WITH CONVERTER ASSEMBLY Click here