HYBRID CONTROL SYSTEM, Diagnostic DTC:P0A93-346

Info Added 2017-08-02

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 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 inverter water pump assembly, cooling fan and cooling system, and detects malfunctions.

B001VDOE03
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

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

  • Power management control ECU

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
      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

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

    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 for DTCs.

      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
      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 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)

    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 the connector connections and contact pressure of the low voltage connectors of the inverter with converter assembly Click here.

      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.

      A00046KE03
      OK
      The connectors are connected securely and there are no contact pressure 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

  4. 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

      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


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


    NG

    CORRECT THE PROBLEM

    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

    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.

    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)

      During Active Test

      		 2500 to 5875 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.


    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).

    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

      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

    REPLACE INVERTER WITH CONVERTER ASSEMBLY Click here

    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. 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 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 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.


    B

    REPLACE HV COOLANT Click here

    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

    COMPLETED

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


    1. A0005OEE01
      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

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


    1. B001VI2

      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.

    NG

    CONNECT SECURELY

    OK

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


    1. Disconnect the A31 power management control ECU connector.

    2. Disconnect the A41 inverter water pump assembly connector.

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

      B001VGRE03
      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
      A31-13 (IWP) - A41-3 (SWP) Power switch off Below 1 Ω
      Standard Resistance (Check for Short)
      Tester Connection Condition Specified Condition
      A31-13 (IWP) or A41-3 (SWP) - Body ground and other terminals Power switch off 10 kΩ or higher

    4. Reconnect the A31 power management control ECU connector.

    5. Reconnect the A41 inverter water pump assembly connector.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    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. Remove the INV W/PMP fuse from the No. 2 engine room relay block.

    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 INV W/PMP fuse.


    NG

    REPLACE POWER MANAGEMENT CONTROL ECU Click here

    OK

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


    1. Disconnect the A31 power management control ECU connector.

    2. Turn the power switch on (IG).

    3. B001VBAE03
      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
      A31-13 (IWP) - H1-6 (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 A31 power management control ECU connector.


    NG

    REPLACE INVERTER WATER PUMP ASSEMBLY Click here

    OK

  16. CHECK POWER MANAGEMENT CONTROL ECU (CHECK WAVEFORM)


    1. Turn the power switch on (IG).

    2. B001VGZE03
      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 A31-13 (IWP) - H1-6 (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 ASSEMBLY Click here

    NG

    REPLACE POWER MANAGEMENT CONTROL ECU Click here

  17. 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

    COMPLETED