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 the alternating current for MG2, MG1, and MGR. The inverter generates heat during the conversion process. Therefore, the inverter is cooled by a special cooling system consisting of an electric 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 (HV CPU) monitors the electric inverter water pump assembly, cooling fan, and cooling system, and detects the following malfunctions.

A01NGU0E03
DTC No. INF Code DTC Detection Condition Trouble Area
P0A93 346 Inverter cooling system malfunction (HV cooling malfunction)

  • Inverter cooling system

  • Inverter water pump assembly

  • Inverter with converter assembly

  • Cooling fan system

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 disconnecting 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.

Tech Tips

Waiting for at least 10 minutes is required to discharge the high-voltage capacitor inside the inverter with converter assembly.

Note

If DTC P0A78-284, 286, P0A79-692, 696, P0A7A-322, 324, P0A94-553 or 557 is output, replace the inverter with converter assembly after this inspection.

PROCEDURE


  1. CHECK DTC OUTPUT (HV)


    1. Connect the intelligent tester 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
      DTC P0A93-346 only is output. A
      Any of the following DTCs are also output. B
      DTC No. Relevant Diagnosis
      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 set due to a malfunction which also causes DTCs in the preceding table to be set. 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 Click here

    A

  2. CHECK CONNECTOR CONNECTION CONDITION (INVERTER WITH CONVERTER ASSEMBLY CONNECTOR)

    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.

      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.

      A01NHWR

    2. Check the connection of the low voltage connector of the inverter with converter assembly.

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

      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.


    NG

    CONNECT SECURELY

    OK

  3. CHECK QUANTITY OF HV COOLANT


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

    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

    C

    INSPECT FOR COOLANT LEAK AND ADD COOLANT

    A

  4. CHECK COOLANT HOSE


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


    NG

    CORRECT THE PROBLEM

    OK

  5. PERFORM ACTIVE TEST USING INTELLIGENT TESTER (CONTROL THE ELECTRIC COOLING FAN)


    1. Connect the intelligent tester 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.

      OK
      The cooling fan rotates.

    5. Turn the power switch off.


    NG

    CHECK COOLING FAN SYSTEM Click here

    OK

  6. READ VALUE USING INTELLIGENT TESTER


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

    2. Connect the intelligent tester 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).

    5. Read the Data List.

      Result
      Result Proceed to
      The difference between "Inverter Coolant Water Temperature" value and other temperatures selected in the list is smaller than 20°C (36°F). A
      The difference between "Inverter Coolant Water Temperature" value and other temperatures selected in the list is at least 20°C (36°F). B

      Note

      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 -50°C (-58°F). The "Inverter Coolant Water Temperature" value displayed on the intelligent tester 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

  7. 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 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 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

    REPLACE INVERTER WATER PUMP ASSEMBLY Click here

    A

  8. 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

  9. 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