HYBRID CONTROL SYSTEM Inverter Low-voltage Circuit

DESCRIPTION

The cause of the malfunction may be the low-voltage circuit.

Check whether there is an open circuit in the inverter +B low-voltage power source system or a problem in the communication between the hybrid vehicle control ECU and inverter.

Related Parts Check
Area Inspection Step
Inverter +B low-voltage power source system check Check for inverter overcurrent malfunction. 1, 2
Communication malfunction between hybrid vehicle control ECU and MG-ECU inside inverter with converter assembly Check for inverter overcurrent malfunction due to communication malfunction. 3, 4
Check for short to ground in inverter +B low-voltage power source system - 5, 6, 7

WIRING DIAGRAM

B002J3HE05

CAUTION / NOTICE / HINT

This step is referenced from the procedures for each DTC.

If the inspection results below are normal, perform the next procedure for the referenced DTC.

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.

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PROCEDURE


  1. CHECK FUSE (PCU)


    1. B002I1OC01
      *1 No. 1 Engine Room Relay Block
      *2 PCU Fuse

      Remove the PCU fuse from the No. 1 engine room relay block.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      PCU fuse terminal Always Below 1 Ω

    3. Install the PCU fuse.

      Result
      Proceed to
      OK
      NG

    NG

    CHECK HARNESS AND CONNECTOR (INVERTER WITH CONVERTER ASSEMBLY - PCU FUSE) Click here

    OK

  2. CHECK HARNESS AND CONNECTOR (INVERTER WITH CONVERTER ASSEMBLY POWER SOURCE CIRCUIT)

    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 A58 inverter with converter assembly connector.

      Click here

    3. B002I76C69
      *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
      A58-10 (GND1) - Body ground Power switch off Below 1 Ω
      A58-11 (GND2) - Body ground Power switch off Below 1 Ω

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

    5. Turn the power switch on (IG).

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      A58-30 (+B) - Body ground Power switch on (IG) Same as auxiliary battery voltage
      A58-31 (+B2) - 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 A58 inverter with converter assembly connector.

      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE POWER SOURCE CIRCUIT

    OK

  3. CHECK HARNESS AND CONNECTOR (HYBRID VEHICLE CONTROL ECU - INVERTER WITH CONVERTER ASSEMBLY)

    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 A58 inverter with converter assembly connector.

    3. Disconnect the A61 hybrid vehicle control ECU connector.

    4. B002I3DC02
      *a

      Front view of wire harness connector

      (to Inverter with Converter Assembly)
      *b

      Rear view of wire harness connector

      (to Hybrid Vehicle Control ECU)

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

      Standard Resistance (Check for Open)
      Tester Connection Condition Specified Condition
      A58-9 (HTM+) - A61-24 (HTM+) Power switch off Below 1 Ω
      A58-20 (HTM-) - A61-25 (HTM-) Power switch off Below 1 Ω
      A58-8 (MTH+) - A61-23 (MTH+) Power switch off Below 1 Ω
      A58-19 (MTH-) - A61-22 (MTH-) Power switch off Below 1 Ω
      A58-26 (REQ+) - A61-31(REQ+) Power switch off Below 1 Ω
      A58-37 (REQ-) - A61-30 (REQ-) Power switch off Below 1 Ω
      A58-7 (CLK+) - A61-33 (CLK+) Power switch off Below 1 Ω
      A58-18 (CLK-) - A61-32 (CLK-) Power switch off Below 1 Ω
      Standard Resistance (Check for Short)
      Tester Connection Condition Specified Condition
      A58-9 (HTM+) or A61-24 (HTM+) - Body ground and other terminals Power switch off 10 kΩ or higher
      A58-20 (HTM-) or A61-25 (HTM-) - Body ground and other terminals Power switch off 10 kΩ or higher
      A58-8 (MTH+) or A61-23 (MTH+) - Body ground and other terminals Power switch off 10 kΩ or higher
      A58-19 (MTH-) or A61-22 (MTH-) - Body ground and other terminals Power switch off 10 kΩ or higher
      A58-26 (REQ+) or A61-31(REQ+) - Body ground and other terminals Power switch off 10 kΩ or higher
      A58-37 (REQ-) or A61-30 (REQ-) - Body ground and other terminals Power switch off 10 kΩ or higher
      A58-7 (CLK+) or A61-33 (CLK+) - Body ground and other terminals Power switch off 10 kΩ or higher
      A58-18 (CLK-) or A61-32 (CLK-) - Body ground and other terminals Power switch off 10 kΩ or higher

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

    6. Turn the power switch on (IG).

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      A58-9 (HTM+) or A61-24 (HTM+) - Body ground Power switch on (IG) Below 1 V
      A58-20 (HTM-) or A61-25 (HTM-) - Body ground Power switch on (IG) Below 1 V
      A58-8 (MTH+) or A61-23 (MTH+) - Body ground Power switch on (IG) Below 1 V
      A58-19 (MTH-) or A61-22 (MTH-) - Body ground Power switch on (IG) Below 1 V
      A58-26 (REQ+) or A61-31(REQ+) - Body ground Power switch on (IG) Below 1 V
      A58-37 (REQ-) or A61-30 (REQ-) - Body ground Power switch on (IG) Below 1 V
      A58-7 (CLK+) or A61-33 (CLK+) - Body ground Power switch on (IG) Below 1 V
      A58-18 (CLK-) or A61-32 (CLK-) - Body ground Power switch on (IG) Below 1 V

      Note

      Turning the power switch on (IG) with the hybrid vehicle control ECU and inverter with converter assembly connectors disconnected causes other DTCs to be stored. Clear the DTCs after performing this inspection.

    8. Turn the power switch off.

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

    10. Reconnect the A61 hybrid vehicle control ECU connector.

    11. Reconnect the A58 inverter with converter assembly connector.

      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  4. CHECK HYBRID VEHICLE CONTROL ECU


    1. Disconnect the A61 hybrid vehicle control ECU connector.

    2. B002IF7C02
      *a

      Component without harness connected

      (Hybrid Vehicle Control ECU)

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A61-24 (HTM+) - A61-25 (HTM-) Power switch off 80 to 170 Ω
      A61-23 (MTH+) - A61-22 (MTH-) Power switch off 80 to 170 Ω
      A61-31 (REQ+) - A61-30 (REQ-) Power switch off 80 to 170 Ω
      A61-33 (CLK+) - A61-32 (CLK-) Power switch off 80 to 170 Ω

    3. Reconnect the A61 hybrid vehicle control ECU connector.

      Result
      Proceed to
      OK
      NG

    OK

    INVERTER LOW-VOLTAGE CIRCUIT NORMAL (PERFORM NEXT STEP FOR REFERENCED DTC)

    NG

    REPLACE HYBRID VEHICLE CONTROL ECU Click here

  5. CHECK HARNESS AND CONNECTOR (INVERTER WITH CONVERTER ASSEMBLY - PCU 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 A58 inverter with converter assembly connector.

      Click here

    3. B002I76C70
      *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
      A58-30 (+B) - Body ground Power switch off 10 kΩ or higher
      A58-31 (+B2) - Body ground Power switch off 10 kΩ or higher

    4. Reconnect the A58 inverter with converter assembly connector.

      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR Click here

    OK

  6. REPLACE INVERTER WITH CONVERTER ASSEMBLY

    Click here

    Result
    Proceed to
    NEXT

    NEXT

    REPLACE FUSE (PCU)

  7. REPAIR OR REPLACE HARNESS OR CONNECTOR

    Result
    Proceed to
    NEXT

    NEXT

    REPLACE FUSE (PCU)