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 MG1 and 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 electric water pump, cooling fan, and cooling system, and detects the following malfunctions.

B005XUNE05
Text in Illustration
*1 Inverter Water Pump Assembly *2 Inverter Reserve Tank Assembly
*3 Inverter with Converter Assembly *4 Radiator Assembly (HV)
*5 Hybrid Vehicle Transaxle Assembly - -
DTC No. INF Code DTC Detection Condition Trouble Area
P0A93 346

HV cooling temperature increases and 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

Related Data List
DTC No. INF Code Data List Item
P0A93 346
  • Inverter Coolant Water Temperature

  • Inverter Temp-(MG1)

  • Inverter Temp-(MG2)

  • DC/DC Cnv Temp (Upper)

  • DC/DC Cnv Temp (Lower)

  • Inverter W/P Revolution

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.

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)" and " DC/DC Cnv Temp (Lower)" 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
      Result Proceed to
      Not blocked. A
      Is/was blocked. B

      Tech Tips

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


    B
    A
  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 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
    A
  3. CHECK CONNECTOR CONNECTION CONDITION (INVERTER WITH CONVERTER ASSEMBLY CONNECTOR)

    CAUTION:

    Be sure to wear insulated gloves.


    1. A005CAR

      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.

    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
    OK
  4. CHECK QUANTITY OF HV COOLANT


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

    2. Check for 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 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
    C
    A
  5. CHECK COOLANT HOSE


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


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


    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.

      OK
      The cooling fan rotates.
    5. Turn the power switch off.


    NG
    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.

    • Be sure that the coolant level is above the low line of the inverter reserve tank assembly.

    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.

    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
      Tester Display Switch Condition Specified Condition
      Inverter W/P Revolution Power switch on (IG) 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
    OK
  8. READ VALUE USING GTS


    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).

    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 (36°F) or more. 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 -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
    A
  9. 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. Read the freeze frame data Ambient Temperature using the GTS.

    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 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 set.

      • A DTC is set when the water pump 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
    A
  10. 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
  11. CHECK CONNECTOR CONNECTION CONDITION (POWER MANAGEMENT CONTROL ECU CONNECTOR)


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

      A005DLOE01
      Text in Illustration
      *A for LHD *B for RHD
      OK
      The connectors are connected securely and there are no contact pressure problems.

    NG
    OK
  12. CHECK CONNECTOR CONNECTION CONDITION (INVERTER WATER PUMP ASSEMBLY CONNECTOR)


    1. A005BDE

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

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

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


    1. Disconnect the A21 power management control ECU connector.

    2. Disconnect the g1 inverter water pump assembly connector.

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

      A005EIUE02
      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 Condition Specified Condition
      g1-3 (SWP) - A21-13 (IWP) Power switch off Below 1 Ω
      Standard Resistance (Check for Short)
      Tester Connection Condition Specified Condition
      g1-3 (SWP) or A21-13 (IWP) - Body ground and other terminals Power switch off 10 kΩ or higher
    4. Reconnect the A21 power management control ECU connector.

    5. Reconnect the g1 inverter water pump assembly connector.


    NG
    OK
  14. 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 assembly may not operate.


    1. Connect the GTS to the DLC3.

    2. A005EU8E02
      Text in Illustration
      *1 Engine Room Relay Block and Junction Block Assembly
      *2 IGCT No. 3 Fuse

      Remove the IGCT No. 3 fuse from the engine room relay block and junction block assembly.

    3. Turn the power switch on (IG).

    4. Enter the following menus: Powertrain / Hybrid Control / ECU Data List / 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. Install the IGCT No. 3 fuse.


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


    1. Disconnect the A21 power management control ECU connector.

    2. Turn the power switch on (IG).

    3. A0059WCE02
      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 Condition Specified Condition
      A21-13 (IWP) - L5-6 (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 A21 power management control ECU connector.


    NG
    OK
  16. CHECK POWER MANAGEMENT CONTROL ECU


    1. Turn the power switch on (IG).

    2. A005AE2E02
      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 A21-13 (IWP) - L5-6 (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
    NG