HYBRID CONTROL SYSTEM, Diagnostic DTC:P0A93-346

DTC Code DTC Name
P0A93-346 Inverter Cooling System Performance

DESCRIPTION

The inverter converts the high-voltage direct current of the HV battery into alternating current for generator (MG1) and motor (MG2). The inverter generates heat during the conversion process. Therefore, the inverter is cooled by a special cooling system consisting of the inverter water pump assembly, the cooling fan, and a radiator. This cooling system is independent of the engine cooling system. The power management control ECU monitors the inverter water pump assembly, cooling fan and cooling system, and detects malfunctions.

B003YRRC01
*A for LHD *B for RHD
*1 Inverter Water Pump Assembly *2 Inverter Reserve Tank Assembly
*3 Inverter with Converter Assembly *4 Radiator Assembly (HV)
*5 Hybrid Vehicle Transmission Assembly - -
DTC No. Detection Item DTC Detection Condition Trouble Area MIL Warning Indicate
P0A93-346 Inverter Cooling System Performance

Inverter cooling system (W/P) malfunction

Inverter coolant temperature increases as well as the temperature of any inverter with converter assembly related parts increases.

(1 trip detection logic)

  • Inverter cooling system

  • Inverter water pump assembly

  • Inverter with converter assembly

  • Cooling fan system

  • Wire harness or connector

  • Power management control ECU

 Comes on

Master Warning Light:

Comes on
Related Data List
DTC No. ECU Data List
P0A93-346

  • Inverter Coolant Water Temperature

  • Inverter Temp- (MG2)

  • Inverter Temp- (MG1)

  • DC/DC Cnv Temp (Upper)

  • DC/DC Cnv Temp (Lower)

  • Engine Coolant Temp

  • Inverter W/P Revolution
Related Active Test
DTC No. Active Test
P0C73-776 Activate the Water Pump

WIRING DIAGRAM

Refer to the wiring diagram for DTC P0C73-776.

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

  • 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

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


  1. Perform a road test according to the freeze frame data "Vehicle Spd" for approximately 15 minutes.

    During the road test, check Data List items "Inverter Coolant Water Temperature", "Inverter Temp-(MG2)", "Inverter Temp- (MG1)", "DC/DC Cnv Temp (Upper)", " DC/DC Cnv Temp (Lower)" and "Engine Coolant Temp" to prevent them from overheating.

PROCEDURE


  1. CHECK VEHICLE CONDITION


    1. Make sure that the front side of the radiator grille is not blocked with anything.

    2. Ask the customer if the front side of the radiator grille was blocked with anything.

      Result
      Proceed to
      Not blocked.
      Is/was blocked.

      Tech Tips

      If the radiator grille is blocked, the inverter coolant temperature will increase and this DTC may be stored.


    Is/was blocked.

    IF EQUIPPED, EXPLAIN TO CUSTOMER THAT OPTIONAL COMPONENTS WILL BE REMOVED

    Not blocked.

  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.


      Powertrain > Hybrid Control > Trouble Codes
      Result
      Result Proceed to
      P0A93-346 only is output, or DTCs except the ones in the table below are also output. A
      Any of the following DTCs are also output. B
      Relevant DTC
      P0A02-719 Motor Electronics Coolant Temperature Sensor Circuit Low
      P0A03-720 Motor Electronics Coolant Temperature Sensor Circuit High
      P0C73-776 Motor Electronics Coolant Pump "A" Control Performance
      P314A-828 Inverter Coolant Pump Speed Signal

      Tech Tips

      P0A93-346 may be stored due to a malfunction which also causes DTCs in the preceding table to be stored. 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)

    Result
    Result Proceed to
    OK A
    NG (The connector is not connected securely.) B
    NG (The terminals are not making secure contact or are deformed, or water or foreign matter exists in the connector.) C

    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. Check connection condition of the low voltage connector of the inverter with converter assembly and the contact pressure of each terminal. Check the terminals for deformation, and check the connector for water ingress and foreign matter.

      Click here

      A0020YPC01
      *A for LHD *B for RHD

      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.

      OK
      - The connector is connected securely.
      - The terminals are not deformed and are connected securely.
      - No water or foreign matter in the connector.
      Result
      Result Proceed to
      OK A
      NG (The connector is not connected securely.) B
      NG (The terminals are not making secure contact or are deformed, or water or foreign matter exists in the connector.) C

      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.


    B

    CONNECT SECURELY

    C

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    A

  4. CHECK QUANTITY OF HV COOLANT

    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

    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

      Tech Tips

      After repairing the HV 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

    C

    INSPECT FOR HV COOLANT LEAK AND ADD HV COOLANT

    A

  5. CHECK COOLANT HOSE

    Result
    Proceed to
    OK
    NG

    1. Check that the cooling system hoses are not kinked or clogged.

      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE COOLANT HOSE

    OK

  6. PERFORM ACTIVE TEST USING GTS (CONTROL THE ELECTRIC COOLING FAN)

    Result
    Proceed to
    OK
    NG

    1. Connect the GTS to the DLC3.

    2. Turn the power switch on (IG).

    3. Enter the following menus: Powertrain / Engine and ECT / Active Test / Control the Electric Cooling Fan.

    4. Perform the "Control the Electric Cooling Fan" Active Test.


      Powertrain > Engine and ECT > Active Test
      Tester Display
      Control the Electric Cooling Fan
      OK
      The cooling fan rotates.

    5. Turn the power switch off.

      Result
      Proceed to
      OK
      NG

    NG

    CHECK COOLING FAN SYSTEM Click here

    OK

  7. PERFORM ACTIVE TEST USING GTS (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 GTS to the DLC3.

    2. Turn the power switch on (IG).

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


      Powertrain > Hybrid Control > Active Test
      Tester Display
      Activate the Water Pump

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


      Powertrain > Hybrid Control > Data List
      Tester Display
      Inverter W/P Revolution

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

      Result
      Tester Display Condition Specified Condition
      Inverter W/P Revolution

      Power switch on (IG)

      During Active Test

      		 2375 to 5750 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 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.

      Result
      Proceed to
      OK
      NG

    NG

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

    OK

  8. READ VALUE USING GTS (DATA LIST)


    1. Turn the power switch off and leave the vehicle for at least 1 hour.

    2. Connect the GTS to the DLC3.

    3. Turn the power switch on (IG).

    4. Enter the following menus: Powertrain / Hybrid Control / Data List / Inverter Coolant Water Temperature, Inverter Temp (MG2), Cnv Tmp (Upper), Cnv Temp (Lower), Inverter Temp (MG1).


      Powertrain > Hybrid Control > Data List
      Tester Display
      Inverter Coolant Water Temperature
      Inverter Temp (MG2)
      Cnv Tmp (Upper)
      Cnv Temp (Lower)
      Inverter Temp (MG1)

    5. Read the Data List.

      Result
      Result Proceed to
      Other than below. A
      "Inverter Coolant Water Temperature" value is higher than the displayed temperature of any other Data List item by 20°C (68°F) or more. B

      Tech Tips

      The lower limit temperature that can be displayed for "Inverter Temp- (MG1)", "Inverter Temp- (MG2)", "Cnv Tmp (Upper)" and "Cnv Temp (Lower)" is 15°C (59°F). The lower limit temperature for "Inverter Coolant Water Temperature" is -40°C (-40°F). The "Inverter Coolant Water Temperature" value displayed on the GTS may be lower than the others, but this is not a malfunction.

    6. Turn the power switch off.


    B

    REPLACE INVERTER WITH CONVERTER ASSEMBLY Click here

    A

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

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

    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 item Ambient Temperature using the GTS.


      Powertrain > Hybrid Control > Trouble Codes

    5. Check if the freeze frame data item Ambient Temperature is below the freezing temperature of the HV coolant.

      Result
      Result Proceed to
      Ambient Temperature value is below freezing temperature of the HV coolant. A
      Ambient Temperature value is above 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 water pump impeller cannot rotate due to freezing of the HV coolant.

      • If DTCs are output due to freezing of the LLC, the problem symptom cannot be reproduced. Check the LLC replacement history and whether the LLC was frozen based on the ambient temperature when the DTCs were stored.

    6. Turn the power switch off.


    B

    REPLACE HV COOLANT Click here

    A

  10. REPLACE HV COOLANT

    Result
    Proceed to
    NEXT

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

      Click here

      Result
      Proceed to
      NEXT

    NEXT

    COMPLETED

  11. REPLACE HV COOLANT

    Result
    Proceed to
    NEXT

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

      Click here

      Result
      Proceed to
      NEXT

    NEXT

    COMPLETED

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

    Result
    Proceed to
    OK
    NG

    1. 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.
      B003YJQC01
      *A for LHD *B for RHD
      Result
      Proceed to
      OK
      NG

    NG

    CONNECT SECURELY

    OK

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

    Result
    Proceed to
    OK
    NG

    1. A01MTLF

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

      Click here

      OK
      The connectors are connected securely and there are no contact pressure problems.
      Result
      Proceed to
      OK
      NG

    NG

    CONNECT SECURELY

    OK

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

    Result
    Proceed to
    OK
    NG

    1. Disconnect the A62 power management control ECU connector.

    2. Disconnect the A12 inverter water pump assembly connector.

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

      A01MROLC07
      *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 Condition Specified Condition
      A62-13 (IWP) - A12-3 (SWP) Power switch off Below 1 Ω
      Standard Resistance (Check for Short)
      Tester Connection Condition Specified Condition
      A62-13 (IWP) or A12-3 (SWP) - Body ground and other terminals Power switch off 10 kΩ or higher

    4. Reconnect the A12 inverter water pump assembly connector.

    5. Reconnect the A62 power management control ECU connector.

      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

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

    Result
    Proceed to
    OK
    NG

    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 GTS to the DLC3.

    2. Disconnect the A12 inverter water pump assembly connector.

    3. Turn the power switch on (IG).

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


      Powertrain > Hybrid Control > Data List
      Tester Display
      Inverter W/P Revolution

    5. Read the Data List.

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

    6. Turn the power switch off.

    7. Reconnect the A12 inverter water pump assembly connector.

      Result
      Proceed to
      OK
      NG

    NG

    REPLACE POWER MANAGEMENT CONTROL ECU Click here

    OK

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

    Result
    Proceed to
    OK
    NG

    1. Disconnect the A62 power management control ECU connector.

    2. Turn the power switch on (IG).

    3. A01MS7CC29
      *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 Condition Specified Condition
      A62-13 (IWP) - K32-6 (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. Reconnect the A62 power management control ECU connector.

      Result
      Proceed to
      OK
      NG

    NG

    REPLACE INVERTER WATER PUMP ASSEMBLY Click here

    OK

  17. CHECK POWER MANAGEMENT CONTROL ECU (CHECK WAVEFORM)

    Result
    Proceed to
    OK
    NG

    1. Connect an oscilloscope between the power management control ECU terminals specified in the table below.

    2. Turn the power switch on (IG).

    3. B003YDCC08
      *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 A62-13 (IWP) - K32-6 (E1)
      Equipment Setting 5 V/DIV., 50 ms./DIV.
      Condition Power switch on (IG)
      OK
      Waveform duty ratio is between 3% and 9%.

    4. Turn the power switch off.

      Result
      Proceed to
      OK
      NG

    OK

    REPLACE INVERTER WATER PUMP ASSEMBLY Click here

    NG

    REPLACE POWER MANAGEMENT CONTROL ECU Click here