HYBRID CONTROL SYSTEM, Diagnostic DTC:P0A08-264

Info Added 2017-08-02

DTC Code DTC Name
P0A08-264 DC / DC Converter Status Circuit

DESCRIPTION

The DC/DC converter converts the DC 244.8 V of the HV battery into DC 12 V in order to supply power to areas such as the vehicle's lighting, audio, and ECU systems. In addition, it charges the auxiliary battery. A transistor bridge circuit initially converts DC 244.8 V into alternating current, and a transformer lowers its voltage. Then, it is rectified and smoothed (into DC) and converted into DC 12 V. The DC/DC converter controls the output voltage in order to keep a constant voltage at the terminals of the auxiliary battery.

The power management control ECU uses the NODD signal line to transmit a stop command to the DC/DC converter and receive signals indicating the normal or abnormal condition of the 12 V charging system. If the vehicle is being driven with an inoperative DC/DC converter, the voltage of the auxiliary battery will drop, which will prevent the continued operation of the vehicle. Therefore, the power management control ECU monitors the operation of the DC/DC converter and alerts the driver if it detects a malfunction.

A0004AZE03
DTC No. INF Code DTC Detection Condition Trouble Area
P0A08 264 DC/DC converter malfunction or the auxiliary battery voltage drops to 11 V or less with the power switch on (READY).

  • Wire harness or connector

  • Inverter cooling system

  • Hybrid vehicle transaxle assembly

  • Inverter with converter assembly

  • Fuse (IGCT-MAIN, DC/DC IGCT, DC/DC-S)

  • Fusible link block assembly (DC/DC)

  • No. 3 engine room wire

  • Power management control ECU

WIRING DIAGRAM

A0004D5E12

Refer to the wiring diagram for DTC P0AA6-526 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.

Tech Tips


  • If the DC/DC converter is malfunctioning, the auxiliary battery cannot be charged. Therefore, once the power switch is turned off, it may be impossible to turn it on (READY) again if the auxiliary battery is completely discharged. In this case, charge the auxiliary battery. Be careful as charging is not performed during the inspection.

  • If the power switch turns off immediately after it is turned on (READY), the auxiliary battery voltage may be low. Charge the auxiliary battery.

PROCEDURE


  1. 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
      P0A08-264 only is output, or DTCs except the ones in the table below are also output. A
      Any of the following DTCs including pending DTCs are also output. B
      DTC No. Relevant Diagnosis
      P0A93-346 Inverter Cooling System Performance
      P0A94-547, 548, 549 DC / DC Converter Performance
      P0AA6-526, 613 Hybrid Battery Voltage System Isolation Fault
      P0ADB-227 Hybrid Battery Positive Contactor Control Circuit Low
      P0ADF-229 Hybrid Battery Negative Contactor Control Circuit Low
      P0AE6-225 Hybrid Battery Precharge Contactor Control Circuit Low
      P0C73-776 Motor Electronics Coolant Pump "A" Control Performance
      P3004-131, 803 High Voltage Power Resource
      P314A-828 Inverter Coolant Pump Speed Signal

    5. Turn the power switch off.


    B

    GO TO DTC CHART (HYBRID CONTROL SYSTEM) Click here

    A

  2. CHECK FUSE (DC/DC-S)


    1. A0004Y0E04
      Text in Illustration
      *1 Engine Room Relay Block and Junction Block Assembly
      *2 DC/DC-S Fuse

      Remove the DC/DC-S fuse from the engine room relay block and junction block assembly.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      DC/DC-S fuse terminals Always Below 1 Ω

    3. Install the DC/DC-S fuse.


    NG

    CHECK HARNESS AND CONNECTOR (INVERTER WITH CONVERTER ASSEMBLY - DC/DC-S FUSE) Click here

    OK

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


    1. A0009DG

      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

  4. 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

  5. CHECK FUSIBLE LINK BLOCK ASSEMBLY (DC/DC)


    1. Check the fusible link block assembly (DC/DC) in the engine room relay block and junction block assembly for improper installation.

      OK
      The fusible link is installed securely.

    2. Remove the fusible link block assembly from the engine room relay block and junction block assembly.

    3. A0004DAE04
      Text in Illustration
      *1 Fusible Link Block Assembly

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      Fusible link block assembly (DC/DC) 1 - 2 Always Below 1 Ω

    4. Install the fusible link block assembly.


    NG

    REPLACE FUSIBLE LINK BLOCK ASSEMBLY (DC/DC)

    OK

  6. CHECK CABLE AND WIRE HARNESS

    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. A00056J

      Remove the upper inverter cover (generator cable side) and upper inverter cover (motor cable side) from the inverter with converter assembly.

    3. A00094DE03
      Text in Illustration
      *1 Generator Cable
      *2 Motor Cable

      Using a megohmmeter set to 500 V, measure the insulation resistance according to the value(s) in the table below.

      Note

      Be sure to set the megohmmeter to 500 V when performing this test. Using a setting higher than 500 V can result in damage to the component being inspected.

      Standard Resistance
      Tester Connection Condition Specified Condition
      d1-1 (W) - Body ground and shield ground Power switch off 1 MΩ or higher
      d1-2 (V) - Body ground and shield ground Power switch off 1 MΩ or higher
      d1-3 (U) - Body ground and shield ground Power switch off 1 MΩ or higher
      e1-1 (W) - Body ground and shield ground Power switch off 1 MΩ or higher
      e1-2 (V) - Body ground and shield ground Power switch off 1 MΩ or higher
      e1-3 (U) - Body ground and shield ground Power switch off 1 MΩ or higher

      Tech Tips

      Perform this inspection while the generator cable and motor cable are connected.

    4. Install the upper inverter cover (generator cable side) and upper inverter cover (motor cable side).


    NG

    CHECK HYBRID VEHICLE TRANSAXLE ASSEMBLY (MG1) Click here

    OK

  7. CHECK AMD TERMINAL VOLTAGE (ENGINE ROOM RELAY BLOCK AND JUNCTION BLOCK ASSEMBLY SIDE)

    CAUTION:

    Be sure to wear insulated gloves.


    1. Connect the cable to the negative (-) auxiliary battery terminal.

    2. A0005ODE03

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      1K-1 (AMD) - Body ground Power switch off Same as auxiliary battery voltage

    3. Disconnect the cable from the negative (-) auxiliary battery terminal.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  8. CHECK AMD TERMINAL CONNECTION CONDITION

    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. A0005KE

      Check that the bolt for the AMD terminal (inverter with converter assembly side and engine room relay block and junction block assembly side) is tightened to the specified torque, the AMD terminal (inverter with converter assembly side and engine room relay block and junction block assembly side) is connected securely, and there is no contact problem.

      Torque
      T=18 N*m {184 kgf*cm, 13ft.*lbf } (Inverter with converter assembly side)
      T=8.0 N*m {82 kgf*cm, 71in.*lbf } (Engine room relay block and junction block assembly side)
      Result
      Result Proceed to
      There are no arc marks. The terminal is connected securely and there is no contact problem. A
      There are no arc marks. The terminal is not connected securely and there is a contact problem. B
      There are arc marks. - C

    B

    CONNECT SECURELY

    C

    REPLACE MALFUNCTIONING PARTS

    A

  9. CHECK NO. 3 ENGINE ROOM WIRE

    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. Disconnect No. 3 engine room wire from the AMD terminal (inverter with converter assembly side and engine room relay block and junction block assembly side).

    3. A0008GSE03
      Text in Illustration
      *1 No. 3 Engine Room Wire

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      B1-1 (AMD) - 1K-1 (AMD) Always Below 1 Ω

    4. Connect No. 3 engine room wire.


    NG

    REPLACE NO. 3 ENGINE ROOM WIRE

    OK

  10. CHECK HARNESS AND CONNECTOR (INVERTER WITH CONVERTER ASSEMBLY - DC/DC-S FUSE, DC/DC IGCT FUSE)

    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. Disconnect the A13 inverter with converter assembly connector.

    3. Connect the cable to the negative (-) auxiliary battery terminal.

    4. A0008B5E01
      Text in Illustration
      *a

      Front view of wire harness connector

      (to Inverter with Converter Assembly)

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      A13-3 (S) - Body ground Always Same as auxiliary battery voltage

    5. Turn the power switch on (IG).

    6. A0008I5E01
      Text in Illustration
      *a

      Front view of wire harness connector

      (to Inverter with Converter Assembly)

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      A13-1 (IGCT) - Body ground Power switch on (IG) Same as auxiliary battery voltage

      Note

      Turning the power switch on (IG) with the inverter with converter assembly connector disconnected causes other DTCs to be stored. Clear the DTCs after performing this inspection.

    7. Turn the power switch off.

    8. Disconnect the cable from the negative (-) auxiliary battery terminal.

    9. Reconnect the A13 inverter with converter assembly connector.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  11. CHECK HARNESS AND CONNECTOR (RESISTANCE VALUE OF NODD INSIDE POWER MANAGEMENT CONTROL ECU)

    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. Disconnect the A13 inverter with converter assembly connector.

    3. A0005F6E03
      Text in Illustration
      *a

      Front view of wire harness connector

      (to Inverter with Converter Assembly)

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A13-5 (NODD) - Body ground Power switch off 110 to 150 kΩ

    4. Reconnect the A13 inverter with converter assembly connector.


    NG

    INSPECT POWER MANAGEMENT CONTROL ECU (RESISTANCE VALUE OF NODD INSIDE POWER MANAGEMENT CONTROL ECU) Click here

    OK

  12. CHECK DC/DC CONVERTER FUNCTION

    Tech Tips

    The current at the AMD terminal cannot be measured directly because of space limitations. Measure the current flowing at the auxiliary battery instead.


    1. A000878E02
      *1 Probe Direction
      *2 Current Flowing into Auxiliary Battery

      Connect the AC/DC 400 A probe to the positive auxiliary battery line.

    2. Install the service plug grip.

    3. Connect the cable to the negative (-) auxiliary battery terminal.

    4. Turn the power switch on (READY) and leave the vehicle as it is until the electric current flowing into the auxiliary battery becomes 10 A or less.

      Tech Tips

      If the power switch turns off immediately after it is turned on (READY), auxiliary battery voltage may be low. Recharge the auxiliary battery and perform this procedure again.

    5. A0009KFE02
      *1 Probe Direction
      *2 Current Flowing from Auxiliary Battery

      Measure the current flowing from the auxiliary battery with the power switch on (READY), the headlight position switch and blower motor switch in the HI position, and the rear window defogger turned on.

      Standard Current
      Item Condition Specified Condition
      Current flowing from auxiliary battery

      Power switch on (READY)

      (The headlight position switch and blower motor switch are in the HI position, and the rear window defogger is turned on.)

      0 A or less

      (no current from auxiliary battery)

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

      Standard Voltage
      Item Condition Specified Condition
      Auxiliary battery voltage

      Power switch on (READY)

      (The headlight position switch and blower motor switch are in the HI position, and the rear window defogger is turned on.)

      		 13 to 15 V

    7. Turn the power switch off.


    NG

    REPLACE INVERTER WITH CONVERTER ASSEMBLY Click here

    OK

  13. 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

  14. CHECK COOLANT HOSE


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


    NG

    CORRECT THE PROBLEM

    OK

  15. 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

  16. 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 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 WITH CONVERTER ASSEMBLY Click here

    B

    REPLACE HV COOLANT Click here

  17. CHECK HYBRID VEHICLE TRANSAXLE ASSEMBLY (MG1)

    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. A0004T5

      Remove the upper inverter cover (generator cable side) from the inverter with converter assembly.

    3. A0004NCE04
      Text in Illustration
      *1 Generator Cable

      Disconnect the generator cable from the inverter with converter assembly.

    4. A0005WPE04
      Text in Illustration
      *1 Shield Ground
      *a Generator Cable (Inverter with Converter Assembly Side)

      Using a megohmmeter set to 500 V, measure the insulation resistance according to the value(s) in the table below.

      Note

      Be sure to set the megohmmeter to 500 V when performing this test. Using a setting higher than 500 V can result in damage to the component being inspected.

      Standard Resistance
      Tester Connection Condition Specified Condition
      e1-1 (W) - Body ground and shield ground Power switch off 100 MΩ or higher
      e1-2 (V) - Body ground and shield ground Power switch off 100 MΩ or higher
      e1-3 (U) - Body ground and shield ground Power switch off 100 MΩ or higher

    5. Connect the generator cable.

    6. Install the upper inverter cover.


    NG

    REPLACE HYBRID VEHICLE TRANSAXLE ASSEMBLY Click here

    OK

  18. CHECK HYBRID VEHICLE TRANSAXLE ASSEMBLY (MG2)

    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. A0008L3

      Remove the upper inverter cover (motor cable side) from the inverter with converter assembly.

    3. A00069ME03
      Text in Illustration
      *1 Motor Cable

      Disconnect the motor cable from the inverter with converter assembly.

    4. A0005F7E03
      Text in Illustration
      *1 Shield Ground
      *a Motor Cable (Inverter with Converter Assembly Side)

      Using a megohmmeter set to 500 V, measure the insulation resistance according to the value(s) in the table below.

      Note

      Be sure to set the megohmmeter to 500 V when performing this test. Using a setting higher than 500 V can result in damage to the component being inspected.

      Standard Resistance
      Tester Connection Condition Specified Condition
      d1-1 (W) - Body ground and shield ground Power switch off 100 MΩ or higher
      d1-2 (V) - Body ground and shield ground Power switch off 100 MΩ or higher
      d1-3 (U) - Body ground and shield ground Power switch off 100 MΩ or higher

    5. Connect the motor cable.

    6. Install the upper inverter cover.


    OK

    REPLACE INVERTER WITH CONVERTER ASSEMBLY Click here

    NG

    REPLACE HYBRID VEHICLE TRANSAXLE ASSEMBLY Click here

  19. INSPECT POWER MANAGEMENT CONTROL ECU (RESISTANCE VALUE OF NODD INSIDE POWER MANAGEMENT CONTROL ECU)


    1. A0008APE02
      Text in Illustration
      *a

      Component without harness connected

      (Power Management Control ECU)

      Disconnect the A31, A33, H1 and H2 power management control ECU connectors.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A31-21 (NODD) - H1-6 (E1) Power switch off 110 to 150 kΩ

    3. Reconnect the A31, A33, H1 and H2 power management control ECU connectors.


    OK

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    NG

    REPLACE POWER MANAGEMENT CONTROL ECU Click here

  20. 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

  21. CHECK HARNESS AND CONNECTOR (INVERTER WITH CONVERTER ASSEMBLY - DC/DC-S FUSE)

    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. Disconnect the A13 inverter with converter assembly connector.

    3. A0004Y0E04
      Text in Illustration
      *1 Engine Room Relay Block and Junction Block Assembly
      *2 DC/DC-S Fuse

      Remove the DC/DC-S fuse from the engine room relay block and junction block assembly.

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

      A000932E03
      Text in Illustration
      *1 Engine Room Relay Block and Junction Block Assembly *2 DC/DC-S Fuse
      *a

      Front view of wire harness connector

      (to Inverter with Converter Assembly)

      		 - -
      Standard Resistance
      Tester Connection Condition Specified Condition
      A13-3 (S) or 2 (DC/DC-S fuse) - Body ground and other terminals Power switch off 10 kΩ or higher

    5. Install the DC/DC-S fuse.

    6. Reconnect the A13 inverter with converter assembly connector.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR Click here

    OK

  22. REPLACE INVERTER WITH CONVERTER ASSEMBLY

    Click here


    NEXT

    REPLACE FUSE (DC/DC-S)

  23. REPAIR OR REPLACE HARNESS OR CONNECTOR


    NEXT

    REPLACE FUSE (DC/DC-S)