HYBRID CONTROL SYSTEM, Diagnostic DTC:P0C73-776

DTC Code DTC Name
P0C73-776 Motor Electronics Coolant Pump "A" Control Performance

DESCRIPTION

The inverter water pump assembly transmits rotation speed information to the power management control ECU (HV CPU). The power management control ECU (HV CPU) monitors the speed and detects malfunctions.

DTC No. INF Code DTC Detection Condition Trouble Area
P0C73 776 A speed or intermittent stop malfunction occurs in the inverter water pump assembly.

  • Inverter cooling system

  • Wire harness or connector

  • Inverter water pump assembly

  • Power management control ECU

WIRING DIAGRAM

A003UQEE06

INSPECTION PROCEDURE

PROCEDURE


  1. CHECK QUANTITY OF HV COOLANT


    1. Check the coolant level in the inverter reserve tank assembly.

    2. Check for coolant leaks.

      Result
      Result Proceed to
      Coolant leaks are not evident. A sufficient amount of coolant remains in the inverter reserve tank. A
      Coolant leaks are not evident. No coolant remains in the inverter reserve tank. B
      Coolant leaks are evident. C

      Tech Tips

      After repairing the coolant leaks and adding coolant, perform the "Activate the Water Pump" Active Test (HV Active Test item) and the "Control the Electric Cooling Fan" Active Test (Engine Active Test item) and make sure that there are no malfunctions.


    B

    ADD HV COOLANT Click here

    C

    INSPECT FOR WATER LEAK Click here

    A

  2. CHECK COOLANT HOSE


    1. Check if the hoses of the cooling system are kinked or clogged.


    NG

    CORRECT THE PROBLEM Click here

    OK

  3. CHECK INVERTER WATER PUMP ASSEMBLY

    Note

    Be sure to perform the inspection with the auxiliary battery voltage at 11 V or more.

    Tech Tips

    When the auxiliary battery voltage is low, the inverter water pump assembly may not operate.


    1. Connect the intelligent tester to the DLC3.

    2. Turn the power switch on (IG).

    3. Enter the following menus: Powertrain / Hybrid Control / Data List.

    4. Select Inverter W/P Revolution in the Data List.

    5. Read the Data List.

      OK
      Inverter W/P Revolution is 625 rpm or less.

    6. Turn the power switch off.


    NG

    Click here

    OK

  4. PERFORM ACTIVE TEST USING INTELLIGENT TESTER (ACTIVATE THE WATER PUMP)

    Note

    Be sure to perform the inspection with the auxiliary battery voltage at 11 V or more.

    Tech Tips

    When the auxiliary battery voltage is low, the inverter water pump assembly may not operate.


    1. Connect the intelligent tester to the DLC3.

    2. Turn the power switch on (IG).

    3. Enter the following menus: Powertrain / Hybrid Control / Active Test / Activate the Water Pump.

    4. Select Inverter W/P Revolution in the Data List.

    5. While performing the "Activate the Water Pump" Active Test, check Inverter W/P Revolution in the Data List.

      Result
      Data List Item Specified Condition
      Inverter W/P Revolution 2250 to 5625 rpm

      Tech Tips

      Perform the Active Test with the inverter coolant temperature between -15 and 65°C (5 to 149°F).

    6. Turn the power switch off.


    NG

    Click here

    OK

  5. CHECK HV COOLANT (CHECK FOR CONDITIONS THAT MAY HAVE CAUSED FREEZING)


    1. Connect the intelligent tester to the DLC3.

    2. Turn the power switch on (IG).

    3. Read the freeze frame data Ambient Temperature using the intelligent tester.

    4. Check if the freeze frame data Ambient Temperature is below freezing.

      Result
      Result Proceed to
      Ambient Temperature value is above freezing temperature of the HV coolant A
      Ambient Temperature value is below freezing temperature of the HV coolant B

      Tech Tips


      • HV coolant (SLLC) with a 30% concentration freezes at -15°C (5°F) and HV coolant (SLLC) with a 50% concentration freezes at -35°C (-31°F).

      • If the HV coolant freezes in the HV radiator or inverter water pump assembly, the coolant temperature in the inverter with converter assembly rises because the HV coolant cannot circulate. As a result, a DTC may be set.

      • A DTC is set when the inverter water pump assembly impeller cannot rotate due to freezing of the HV coolant.

      • If a DTC is set due to freezing of HV coolant, the problem cannot be reproduced. Judge whether freezing of HV coolant occurred according to the freeze point of the HV coolant, HV coolant change history and ambient temperature when the DTC was set.

    5. Turn the power switch off.


    B

    Click here

    A

    REPLACE INVERTER WATER PUMP ASSEMBLY Click here

  6. ADD HV COOLANT


    1. Add coolant up to the high level in the reserve tank.


    NEXT

    Click here

  7. INSPECT FOR WATER LEAK


    1. Diagnose and repair the water leak.


    NEXT

    Click here

  8. CORRECT THE PROBLEM


    1. Correct the coolant hose.


    NEXT

    Click here

  9. CHECK CONNECTOR CONNECTION CONDITION (POWER MANAGEMENT CONTROL ECU CONNECTOR)


    1. Check the connections of the power management control ECU connectors.

      A003TI1E01
      Text in Illustration
      *A for LHD *B for RHD
      OK
      The connectors are connected securely and there are no contact problems.

    NG

    CONNECT SECURELY Click here

    OK

  10. CHECK CONNECTOR CONNECTION CONDITION (INVERTER WATER PUMP ASSEMBLY CONNECTOR)


    1. A003SFW

      Check the connection of the inverter water pump assembly connector.

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

    NG

    CONNECT SECURELY Click here

    OK

  11. CHECK HARNESS AND CONNECTOR (POWER MANAGEMENT CONTROL ECU - INVERTER WATER PUMP ASSEMBLY)


    1. Disconnect connector A98 from the power management control ECU.

    2. Disconnect connector Z1 from the inverter water pump assembly.

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

      A003UVYE07
      Text in Illustration
      *a

      Rear view of wire harness connector

      (to Power Management Control ECU)

      		 *b

      Front view of wire harness connector

      (to Inverter Water Pump Assembly)
      Standard Resistance (Check for Open)
      Tester Connection Switch Condition Specified Condition
      Z1-3 (SWP) - A98-13 (IWP) Power switch off Below 1 Ω
      Standard Resistance (Check for Short)
      Tester Connection Switch Condition Specified Condition
      Z1-3 (SWP) or A98-13 (IWP) - Body ground and other terminals Power switch off 10 kΩ or higher

    4. Connect the power management control ECU connector.

    5. Connect the inverter water pump assembly connector.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR Click here

    OK

  12. READ VALUE USING INTELLIGENT TESTER (INVERTER W/P REVOLUTION)


    1. Connect the intelligent tester to the DLC3.

    2. Turn the power switch on (IG).

    3. Enter the following menus: Powertrain / Hybrid Control / ECU Data List.

    4. Select Inverter W/P Revolution in the Data List.

    5. Disconnect connector Z1 from the inverter water pump assembly.

    6. Read the Data List.

      OK
      Inverter W/P Revolution is 125 rpm or less.

    7. Connect the inverter water pump assembly connector.

    8. Turn the power switch off.


    NG

    REPLACE POWER MANAGEMENT CONTROL ECU Click here

    OK

  13. CHECK POWER MANAGEMENT CONTROL ECU


    1. Turn the power switch on (IG).

    2. A003TI4E54
      Text in Illustration
      *a

      Component with Harness Connected

      (Power Management Control ECU)

      While turning the power switch on (IG), check the waveform between the power management control ECU terminals.

      OK
      Waveform duty ratio is between 3% and 9%.

    3. Turn the power switch off.


    NG

    REPLACE POWER MANAGEMENT CONTROL ECU Click here

    OK

    REPLACE INVERTER WATER PUMP ASSEMBLY Click here

  14. CONNECT SECURELY


    1. Connect the power management control ECU connectors securely.


    NEXT

    Click here

  15. CONNECT SECURELY


    1. Connect the inverter water pump assembly connector securely.


    NEXT

    Click here

  16. REPAIR OR REPLACE HARNESS OR CONNECTOR


    1. Repair or replace the wire harness or connector.


    NEXT

    Click here

  17. REPLACE POWER MANAGEMENT CONTROL ECU


    1. Replace the power management control ECU Click here.


    NEXT

    Click here

  18. REPLACE POWER MANAGEMENT CONTROL ECU


    1. Replace the power management control ECU Click here.


    NEXT

    Click here

  19. REPLACE HV COOLANT


    1. Replace the HV coolant with coolant having an appropriate concentration (appropriate freeze point) for the vehicle usage conditions Click here.


    NEXT

  20. CHECK INVERTER WATER PUMP ASSEMBLY


    1. Perform a road test and check that DTCs are not stored.

      OK
      DTCs are not stored.

    NG

    REPLACE INVERTER WATER PUMP ASSEMBLY Click here

    OK

    COMPLETED