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 with motor assembly transmits rotation revolution information to the power management control ECU. The power management control ECU monitors the revolution 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 with motor assembly.

A revolution malfunction (speed is too high/low or stop) or an intermittent stop malfunction (operation stops intermittently when the speed revolution is abnormal) occurs in the inverter water pump with motor assembly.

  • Inverter cooling system

  • Wire harness or connector

  • Inverter water pump with motor assembly

  • Power management control ECU

Tech Tips

The inverter water pump with motor assembly operates when the power switch is on (READY).

Related Data List
DTC No. ECU Data List
P0C73-776

  • Inverter W/P Revolution

  • (Inverter) W/P Run Control Duty

  • Ready Signal
Related Active Test
DTC No. Active Test
P0C73-776 Activate the (Inverter) Water Pump

WIRING DIAGRAM

A000P13E01

CAUTION / NOTICE / HINT

Note

If DTC P0A78-284, 286, P0A7A-322, 324, P0A94-553 or 557 is output, replace the inverter with converter assembly after this inspection.

Tech Tips


  • When an overvoltage condition in the auxiliary battery voltage occurs due to receiving external assistance, etc., control may be stopped temporarily and this DTC may be output due to the self-protection function of the inverter water pump with motor assembly. (When there is no longer an overvoltage condition in the auxiliary battery voltage, control resumes. Therefore, it is not necessary to replace the inverter water pump with motor assembly.)

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


    1. Turn the power switch on (READY) and wait for 120 seconds or more (when the power switch is turned on (READY), the inverter water pump with motor assembly operates).

PROCEDURE


  1. CHECK QUANTITY OF HV COOLANT


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

    2. Check for HV coolant leaks.

      Result
      Result Proceed to
      No leaks are found and coolant level in the inverter reserve tank assembly is above the low line. A
      No leaks are found and coolant level in the inverter reserve tank assembly is below the low line. B
      HV coolant leaks are evident. C

      Note

      The inverter water pump with motor assembly has a protection function that activates when there is an HV coolant leak. Therefore, it is not necessary to replace the inverter water pump with motor assembly unless the cause of the HV coolant leak is the inverter water pump with motor assembly.

      Tech Tips

      After repairing the HV coolant leaks and adding coolant, perform the "Activate the (Inverter) 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

    C

    INSPECT FOR HV COOLANT LEAK AND ADD HV COOLANT

    A

  2. CHECK COOLANT HOSE


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


    NG

    CORRECT THE PROBLEM

    OK

  3. READ VALUE USING GTS (INVERTER W/P REVOLUTION)

    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 with motor assembly may not operate.

    • When the inverter water pump with motor assembly signal line (SWP - IWP) is open or its connection is faulty, the inverter water pump with motor assembly is operated forcibly.


    1. Connect the GTS to the DLC3.

    2. Turn the power switch on (IG).

    3. Enter the following menus: Powertrain / Hybrid Control / Data List / Inverter W/P Revolution.

    4. Read the Data List.

      OK
      Tester Display Switch Condition Specified Condition
      Inverter W/P Revolution Power switch on (IG) 625 rpm or less

      Tech Tips

      When the inverter water pump with motor assembly is not operating, the Data List item "Inverter W/P Revolution" displays a value lower than 625 rpm.

    5. Turn the power switch off.


    NG

    CHECK CONNECTOR CONNECTION CONDITION (POWER MANAGEMENT CONTROL ECU CONNECTOR) Click here

    OK

  4. CLEAR DTC


    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.

    5. Clear DTCs and freeze frame data.

    6. Turn the power switch off.


    NEXT

  5. PERFORM ACTIVE TEST USING GTS (ACTIVATE THE (INVERTER) 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 with motor assembly may not operate.


    1. Connect the GTS to the DLC3.

    2. Turn the power switch on (IG).

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

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

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

      OK
      Tester Display Switch Condition Specified Condition
      Inverter W/P Revolution Power switch on (IG) 2750 to 6000 rpm

      Tech Tips


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

      • When the inverter water pump with motor assembly is not operating, the Data List item "Inverter W/P Revolution" displays a value lower than 625 rpm.

    6. Turn the power switch off.


    NG

    CHECK CONNECTOR CONNECTION CONDITION (POWER MANAGEMENT CONTROL ECU CONNECTOR) Click here

    OK

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


    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 the freeze frame data Ambient Temperature using the GTS.

    5. 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 HV water pump, the coolant temperature in the inverter with converter assembly rises because the HV coolant cannot circulate. As a result, a DTC may be stored.

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

      • If a DTC is stored 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 stored.

    6. Turn the power switch off.


    A

    REPLACE INVERTER WATER PUMP WITH MOTOR ASSEMBLY Click here

    B

    REPLACE HV COOLANT

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


    1. B002B9CE01
      Text in Illustration
      *A for LHD
      *B for RHD

      Check the connector connections and contact pressure of the relevant terminals for the power management control ECU connectors Click here.

      OK
      The connectors are connected securely and there are no contact pressure problems.

    NG

    CONNECT SECURELY

    OK

  8. CHECK CONNECTOR CONNECTION CONDITION (INVERTER WATER PUMP WITH MOTOR ASSEMBLY CONNECTOR)


    1. A000NUC

      Check the connector connections and contact pressure of the relevant terminals for the inverter water pump with motor assembly connector Click here.

      OK
      The connectors are connected securely and there are no contact pressure problems.

    NG

    CONNECT SECURELY

    OK

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


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

    2. Disconnect the connector from the inverter water pump with motor assembly.

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

      A000QZJE02
      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 with Motor Assembly)
      Standard Resistance (Check for Open)
      Tester Connection Switch Condition Specified Condition
      A35-13 (IWP) - A26-3 (SWP) Power switch off Below 1 Ω
      Standard Resistance (Check for Short)
      Tester Connection Switch Condition Specified Condition
      A35-13 (IWP) or A26-3 (SWP) - 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 with motor assembly connector.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  10. READ VALUE USING GTS (INVERTER W/P REVOLUTION)

    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 with motor assembly may not operate.


    1. Connect the GTS to the DLC3.

    2. A000OLGE01
      Text in Illustration
      *1 No. 1 Engine Room Relay Block and Junction Block Assembly
      *2 INV W/P Fuse

      Remove the INV W/P fuse from the No. 1 engine room relay block and junction block assembly.

    3. Turn the power switch on (IG).

    4. Enter the following menus: Powertrain / Hybrid Control / Data List / Inverter W/P Revolution.

    5. Read the Data List.

      OK
      Tester Display Switch Condition Specified Condition
      Inverter W/P Revolution Power switch on (IG) 125 rpm or less

    6. Turn the power switch off.

    7. Install the INV W/P fuse.


    NG

    REPLACE POWER MANAGEMENT CONTROL ECU Click here

    OK

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


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

    2. Turn the power switch on (IG).

    3. A000RJHE02
      Text in Illustration
      *a

      Rear view of wire harness connector

      (to Power Management Control ECU)

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

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      A35-13 (IWP) - N91-6 (E1) Power switch on (IG) 11 to 14 V

      Note

      Turning the power switch on (IG) with the power management control ECU connector disconnected causes other DTCs to be stored. Clear the DTCs after performing this inspection.

    4. Turn the power switch off.

    5. Connect the power management control ECU connector.


    NG

    REPLACE INVERTER WATER PUMP WITH MOTOR ASSEMBLY Click here

    OK

  12. CHECK POWER MANAGEMENT CONTROL ECU (CHECK WAVEFORM)


    1. Turn the power switch on (IG).

    2. A000O9FE02
      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.

      Item Content
      Terminal A35-13 (IWP) - N91-6 (E1)
      Equipment Setting 5 V/DIV., 50 ms./DIV.
      Condition Power switch on (IG)
      OK
      Waveform duty ratio is between 3% and 9%.

    3. Turn the power switch off.


    OK

    REPLACE INVERTER WATER PUMP WITH MOTOR ASSEMBLY Click here

    NG

    REPLACE POWER MANAGEMENT CONTROL ECU Click here