HYBRID CONTROL SYSTEM ECU Power Source Circuit

DESCRIPTION

With the power switch is turned on (IG), the certification ECU (smart key ECU assembly) sends current to the IG1D terminal and turns the IG2 main relay on.

In this way, a power source is supplied to the IG2 terminal of the of the EV control ECU.

If the power switch is on (IG), the EV control ECU applies current to the MREL terminal to turn the IGCT relay on. This supplies power to the +B1 and +B2 terminals.

WIRING DIAGRAM

Refer to the wiring diagram for DTC P0A08-264.

A01MH2JE02

CAUTION / NOTICE / HINT

Note

When the vehicle is parked with the power switch off, if the FC control ECU judges that the FC stack temperature will go below 0°C (32°F), it activates the FC air compressor, hydrogen pump and FC cooling water pump for a maximum of 180 seconds and drains water from the FC stack assembly. When performing inspection or repairs with the power switch off (not on (IG) or on (READY)), disconnect the cable from the negative (-) auxiliary battery terminal before performing work (If the auxiliary battery voltage is needed to conduct inspection, warm up the FC system beforehand).

PROCEDURE


  1. CHECK TERMINAL VOLTAGE (+B1, +B2 VOLTAGE)


    1. Turn the power switch on (IG).

    2. A01MG4FC93
      *a

      Component with harness connected

      (EV Control ECU)

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      A27-4 (+B1) - Body ground Power switch on (IG) 11 to 14 V
      A28-1 (+B2) - Body ground Power switch on (IG) 11 to 14 V

    3. Turn the power switch off.

      Result
      Proceed to
      OK
      NG

    NG

    CHECK EV CONTROL ECU (MREL VOLTAGE) Click here

    OK

  2. CHECK TERMINAL VOLTAGE (IG2 VOLTAGE)


    1. Turn the power switch on (IG).

    2. A01MG4FC73
      *a

      Component with harness connected

      (EV Control ECU)

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      A28-3 (IG2) - Body ground Power switch on (IG) 11 to 14 V

    3. Turn the power switch off.

      Result
      Proceed to
      OK
      NG

    NG

    CHECK INTEGRATION RELAY (SOURCE VOLTAGE) Click here

    OK

  3. CHECK HARNESS AND CONNECTOR (EV CONTROL ECU - BODY GROUND)


    1. Disconnect the EV control ECU connectors.

    2. A01MHD8C37
      *a

      Rear view of wire harness connector

      (to EV Control ECU)

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      G45-5 (E01) - Body ground Always Below 1 Ω
      G45-6 (E1) - Body ground Always Below 1 Ω
      G46-4 (E12) - Body ground Always Below 1 Ω
      G46-5 (E02) - Body ground Always Below 1 Ω

    3. Reconnect the EV control ECU connectors.

      Result
      Proceed to
      OK
      NG

    OK

    GO TO PROBLEM SYMPTOMS TABLE

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

  4. CHECK INTEGRATION RELAY (SOURCE VOLTAGE)


    1. Remove the No.1 integration relay from the motor compartment relay block.

    2. A01MHFRC02
      *1 No. 1 Integration Relay
      *a

      Front view of wire harness connector

      (to No. 1 Integration relay)

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      1C-1 - Body ground Power switch off 11 to 14 V

    3. Install the No.1 integration relay.

      Result
      Proceed to
      OK
      NG

    NG

    CHECK FUSIBLE LINK (P/I) Click here

    OK

  5. CHECK FUSE (IG2 NO.2)


    1. A01MIH4C02
      *1 Motor Compartment Relay Block
      *2 IG2 NO.2 Fuse

      Remove the IG2 NO.2 fuse from the motor compartment relay block.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      IG2 NO.2 fuse terminals Always Below 1 Ω

    3. Install the IG2 NO.2 fuse.

      Result
      Proceed to
      OK
      NG

    NG

    REPLACE FUSES (IG2 NO.2)

    OK

  6. INSPECT NO.1 INTEGRATION RELAY (IG2 MAIN RELAY)


    1. Remove the No.1 integration relay from the motor compartment relay block.

    2. Inspect the IG2 MAIN relay.

      Click here

    3. Install the No.1 integration relay.

      Result
      Proceed to
      OK
      NG

    NG

    REPLACE NO.1 INTEGRATION RELAY Click here

    OK

  7. CHECK HARNESS AND CONNECTOR (NO.1 INTEGRATION RELAY - BODY GROUND)


    1. Remove the No.1 integration relay from the motor compartment relay block.

    2. A01MJ8SC02
      *1 No. 1 Integration Relay
      *a

      Front view of wire harness connector

      (to No. 1 Integration relay)

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      1B-3 - Body ground Power switch off Below 1 Ω

    3. Install the No.1 integration relay.

      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  8. CHECK HARNESS AND CONNECTOR (NO.1 INTEGRATION RELAY - EV CONTROL ECU)


    1. Remove the No.1 integration relay from the motor compartment relay block.

    2. Disconnect the EV control ECU connectors.

      A01MG0LC02
      *1 No. 1 Integration Relay - -
      *a

      Front view of wire harness connector

      (to No. 1 Integration relay)

      		 *b

      Rear view of wire harness connector

      (to EV Control ECU)

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      1B-4 - A28-3 (IG2) Power switch off Below 1 Ω
      1B-4 or A28-3 (IG2) - Body ground Power switch off 10 kΩ or higher

    4. Reconnect the EV control ECU connectors.

    5. Install the No.1 integration relay.

      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  9. CHECK HARNESS AND CONNECTOR (NO.1 INTEGRATION RELAY - SMART KEY ECU ASSEMBLY)


    1. Remove the No.1 integration relay from the motor compartment relay block.

    2. Disconnect the certification ECU (smart key ECU assembly) connector.

      A01MI4GC02
      *1 No. 1 Integration Relay - -
      *a

      Front view of wire harness connector

      (to No. 1 Integration relay)

      		 *b

      Front view of wire harness connector

      (to Certification ECU (Smart Key ECU Assembly))

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      1B-2 - G40-3 (IG1D) Power switch off Below 1 Ω
      1B-2 or G40-3 (IG1D) - Body ground Power switch off 10 kΩ or higher

    4. Reconnect the certification ECU (smart key ECU assembly) connector.

    5. Install the No.1 integration relay.

      Result
      Proceed to
      OK
      NG

    OK

    CHECK ENTRY AND START SYSTEM Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

  10. CHECK FUSIBLE LINK (P/I)


    1. A01MJ3AC02
      *1 Motor Compartment Relay Block
      *2 Fusible Link (P/I)

      Remove the fusible link (P/I) from the motor compartment relay block.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      Fusible link (P/I) fuse terminals Always Below 1 Ω

    3. Install the fusible link (P/I).

      Result
      Proceed to
      OK
      NG

    OK

    REPAIR OR REPLACE HARNESS OR CONNECTOR (NO.1 INTEGRATION RELAY - AUXILIARY BATTERY)

    NG

    REPLACE FUSIBLE LINK (P/I)

  11. CHECK EV CONTROL ECU (MREL VOLTAGE)


    1. Turn the power switch on (IG).

    2. A01MG4FC94
      *a

      Component with harness connected

      (EV Control ECU)

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      A27-6 (MREL) - Body ground Power switch on (IG) 11 to 14 V

    3. Turn the power switch off.

      Result
      Proceed to
      OK
      NG

    NG

    REPLACE EV CONTROL ECU Click here

    OK

  12. CHECK FUSE (PM-IGCT)


    1. A01MGUAC02
      *1 Motor Compartment Relay Block
      *2 PM-IGCT Fuse

      Remove the PM-IGCT fuse from the motor compartment relay block.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      PM-IGCT fuse terminals Always Below 1 Ω

    3. Install the PM-IGCT fuse.

      Result
      Proceed to
      OK
      NG

    NG

    CHECK HARNESS AND CONNECTOR (EV CONTROL ECU - MOTOR COMPARTMENT RELAY BLOCK) Click here

    OK

  13. CHECK FUSE (IGCT NO.1)


    1. A01MI8IC02
      *1 Motor Compartment Relay Block
      *2 IGCT NO.1 Fuse

      Remove the IGCT NO.1 fuse from the motor compartment relay block.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      IGCT NO.1 fuse terminals Always Below 1 Ω

    3. Install the IGCT NO.1 fuse.

      Result
      Proceed to
      OK
      NG

    NG

    CHECK HARNESS AND CONNECTOR (MOTOR COMPARTMENT RELAY BLOCK) Click here

    OK

  14. INSPECT IGCT NO. 1 RELAY (IGCT NO.1)


    1. Remove the IGCT NO.1 relay from the motor compartment relay block.

    2. A01MILMC18
      *1 IGCT NO.1 Relay

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      3 - 5 Auxiliary battery voltage not applied between terminals 1 and 2 10 kΩ or higher
      Auxiliary battery voltage applied between terminals 1 and 2 Below 1 Ω

    3. Install the IGCT NO.1 relay.

      Result
      Proceed to
      OK
      NG

    NG

    REPLACE IGCT NO. 1 RELAY

    OK

  15. CHECK HARNESS AND CONNECTOR (EV CONTROL ECU - MOTOR COMPARTMENT RELAY BLOCK)


    1. A01MGUAC03
      *1 Motor Compartment Relay Block
      *2 PM-IGCT Fuse

      Remove the PM-IGCT fuse from the motor compartment relay block.

    2. Disconnect the EV control ECU connectors.

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

      A01MFRGC02
      *1 Motor Compartment Relay Block *2 PM-IGCT Fuse Holder
      *a

      Rear view of wire harness connector

      (to EV Control ECU)

      		 - -
      Standard Resistance
      Tester Connection Condition Specified Condition
      A27-4 (+B1) - 2 (PM-IGCT fuse holder) Always Below 1 Ω
      A28-1 (+B2) - 2 (PM-IGCT fuse holder) Always Below 1 Ω

    4. Install the PM-IGCT fuse.

    5. Reconnect the EV control ECU connectors.

      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  16. CHECK HARNESS AND CONNECTOR (MOTOR COMPARTMENT RELAY BLOCK)


    1. A01MHLEC02
      *1 Motor Compartment Relay Block
      *2 IGCT NO.1 Fuse
      *3 IGCT NO.1 Relay
      *4 PM-IGCT Fuse

      Remove the IGCT NO.1 fuse, PM-IGCT fuse and IGCT NO.1 relay from the motor compartment relay block.

    2. A01MHTAC02
      *1 Motor Compartment Relay Block
      *2 IGCT NO.1 Fuse Holder
      *3 IGCT NO.1 Relay Holder
      *4 PM-IGCT Fuse Holder

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      3 (IGCT NO.1 relay holder) - 2 (IGCT NO.1 fuse holder) Always Below 1 Ω
      5 (IGCT NO.1 relay holder) - 1 (PM-IGCT fuse holder) Always Below 1 Ω

    3. Install the IGCT NO.1 fuse, PM-IGCT fuse and IGCT NO.1 relay.

      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  17. CHECK HARNESS AND CONNECTOR (EV CONTROL ECU - MOTOR COMPARTMENT RELAY BLOCK)


    1. Remove the IGCT NO.1 relay from the motor compartment relay block.

    2. Disconnect the EV control ECU connectors.

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

      A01MFIXC04
      *1 Motor Compartment Relay Block *2 IGCT NO.1 Relay Holder
      *a

      Rear view of wire harness connector

      (to EV Control ECU)

      		 - -
      Standard Resistance
      Tester Connection Condition Specified Condition
      A27-6 (MREL) - 1 (IGCT NO.1 relay holder) Always Below 1 Ω
      A27-6 (MREL) or 1 (IGCT NO.1 relay holder) - Body ground and other terminals Always 10 kΩ or higher

    4. Install the IGCT NO.1 relay.

    5. Reconnect the EV control ECU connectors.

      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  18. CHECK HARNESS AND CONNECTOR (MOTOR COMPARTMENT RELAY BLOCK - BODY GROUND)


    1. Remove the IGCT NO.1 relay from the motor compartment relay block.

    2. A01MGCMC02
      *1 Motor Compartment Relay Block
      *2 IGCT NO.1 Relay Holder

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      2 (IGCT NO.1 relay holder) - Body ground Always Below 1 Ω

    3. Install the IGCT NO.1 relay.

      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  19. CHECK HARNESS AND CONNECTOR (MOTOR COMPARTMENT RELAY BLOCK)


    1. Disconnect the No. 2 motor compartment main wire from the AMD terminal (motor compartment relay block side).

    2. A01MIOCC02
      *1 Motor Compartment Relay Block
      *2 AMD Terminal
      *3 IGCT NO.1 Fuse

      Remove the IGCT NO.1 fuse from the motor compartment relay block.

    3. A01MGLXC02
      *1 Motor Compartment Relay Block
      *2 IGCT NO.1 Fuse Holder

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      1C-1 (AMD) - 1 (IGCT NO.1 fuse holder) Always Below 1 Ω

    4. Reconnect the No. 2 motor compartment main wire.

    5. Install the IGCT NO.1 relay.

      Result
      Proceed to
      OK
      NG

    OK

    CHECK INTERMITTENT PROBLEMS

    NG

  20. CHECK FUSES (DC/DC)

    Result
    Proceed to
    OK
    NG

    CAUTION:

    Be sure to wear insulated gloves.


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

    2. B000ZTNE01

      Disconnect the 1E motor compartment relay block terminal.

    3. Disconnect the 1F motor compartment relay block terminal.

    4. B000ZP3C02
      *1 Motor Compartment Relay Block

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      1E-1 - 1F-1 Always Below 1 Ω

    5. Reconnect the 1F motor compartment relay block terminal.

    6. Reconnect the 1E motor compartment relay block terminal.

    7. Reconnect the cable to the negative (-) auxiliary battery terminal.

      Result
      Proceed to
      OK
      NG

    OK

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    NG

    REPLACE FUSES (DC/DC)

  21. CHECK HARNESS AND CONNECTOR (MOTOR COMPARTMENT RELAY BLOCK)


    1. A01MHLEC02
      *1 Motor Compartment Relay Block
      *2 IGCT NO.1 Fuse
      *3 IGCT NO.1 Relay
      *4 PM-IGCT Fuse

      Remove the IGCT NO.1 fuse, PM-IGCT fuse and IGCT NO.1 relay from the motor compartment relay block.

    2. A01MHTAC02
      *1 Motor Compartment Relay Block
      *2 IGCT NO.1 Fuse Holder
      *3 IGCT NO.1 Relay Holder
      *4 PM-IGCT Fuse Holder

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      3 (IGCT NO.1 relay holder) or 2 (IGCT NO.1 fuse holder) - Body ground and other terminals Always 10 kΩ or higher
      5 (IGCT NO.1 relay holder) or 1 (IGCT NO.1 fuse holder) - Body ground and other terminals Always 10 kΩ or higher

    3. Install the IGCT NO.1 fuse, PM-IGCT fuse and IGCT NO.1 relay.

      Result
      Proceed to
      OK
      NG

    OK

    REPLACE FUSES (IGCT NO.1)

    NG

  22. REPAIR OR REPLACE HARNESS OR CONNECTOR

    Result
    Proceed to
    NEXT

    NEXT

    REPLACE FUSES (IGCT NO.1)

  23. CHECK HARNESS AND CONNECTOR (EV CONTROL ECU - MOTOR COMPARTMENT RELAY BLOCK)


    1. A01MGUAC04
      *1 Motor Compartment Relay Block
      *2 PM-IGCT Fuse

      Remove the PM-IGCT fuse from the motor compartment relay block.

    2. Disconnect the EV control ECU connectors.

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

      A01MIUGC03
      *1 Motor Compartment Relay Block *2 PM-IGCT Fuse Holder
      *a

      Rear view of wire harness connector

      (to EV Control ECU)

      		 - -
      Standard Resistance
      Tester Connection Condition Specified Condition
      A27-4 (+B1) or 2 (PM-IGCT fuse holder) - Body ground and other terminals Always 10 kΩ or higher
      A28-1 (+B2) or 2 (PM-IGCT fuse holder) - Body ground and other terminals Always 10 kΩ or higher

    4. Install the PM-IGCT fuse.

    5. Reconnect the EV control ECU connectors.

      Result
      Proceed to
      OK
      NG

    OK

    REPLACE FUSES (PM-IGCT)

    NG

  24. REPAIR OR REPLACE HARNESS OR CONNECTOR

    Result
    Proceed to
    NEXT

    NEXT

    REPLACE FUSES (PM-IGCT)