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HYBRID CONTROL SYSTEM ECU Power Source Circuit

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DTC Code DTC Name
  ECU Power Source Circuit
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DESCRIPTION

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

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WIRING DIAGRAM

Refer to the wiring diagram for DTC P0A08-264 (Click here).

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PROCEDURE


  1. Click here

    CHECK HYBRID VEHICLE CONTROL ECU ASSEMBLY (+B1, +B2 VOLTAGE)


    1. Turn the power switch on (IG).

    2. A0004ZBE02

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      A79-4 (+B1) - Body ground Power switch on (IG) 11 to 14 V
      A78-1 (+B2) - Body ground Power switch on (IG) 11 to 14 V
      Table 1. Text in Illustration
      *a

      Component with harness connected

      (Hybrid Vehicle Control ECU Assembly)

    3. Turn the power switch off.


  2. Click here

    CHECK HARNESS AND CONNECTOR (HYBRID VEHICLE CONTROL ECU ASSEMBLY - BODY GROUND)


    1. Disconnect the H211 and H212 hybrid vehicle control ECU assembly connectors.

    2. A0005X7E02

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      H211-5 (E01) - Body ground Always Below 1 Ω
      H211-6 (E1) - Body ground Always Below 1 Ω
      H212-4 (E12) - Body ground Always Below 1 Ω
      H212-5 (E02) - Body ground Always Below 1 Ω
      Table 2. Text in Illustration
      *a

      Rear view of wire harness connector

      (to Hybrid Vehicle Control ECU Assembly)

    3. Reconnect the H211 and H212 hybrid vehicle control ECU assembly connectors.


    • OK

      GO TO PROBLEM SYMPTOMS TABLE (Click here)

    • NG

      REPAIR OR REPLACE HARNESS OR CONNECTOR

  3. Click here

    CHECK HYBRID VEHICLE CONTROL ECU ASSEMBLY (MREL VOLTAGE)


    1. Turn the power switch on (IG).

    2. A0003WTE02

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      A79-6 (MREL) - Body ground Power switch on (IG) 11 to 14 V
      Table 3. Text in Illustration
      *a

      Component with harness connected

      (Hybrid Vehicle Control ECU Assembly)

  4. Click here

    CHECK FUSE (PM IGCT)


    1. A0008OYE01

      Remove the PM IGCT fuse from the No. 2 engine room 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
      Table 4. Text in Illustration
      *1 No. 2 Engine Room Relay Block
      *2 PM IGCT Fuse

    3. Install the PM IGCT fuse.


  5. Click here

    CHECK FUSE (IGCT-MAIN)


    1. A00042VE03

      Remove the IGCT-MAIN fuse from the No. 2 engine room relay block.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      IGCT-MAIN fuse terminals Always Below 1 Ω
      Table 5. Text in Illustration
      *1 No. 2 Engine Room Relay Block
      *2 IGCT-MAIN Fuse

    3. Install the IGCT-MAIN fuse.


  6. Click here

    INSPECT RELAY (IGCT)


    1. Remove the IGCT relay from the No. 2 engine room relay block.

    2. A0004PBE03

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      3 - 5 Auxiliary battery voltage is not applied between terminals 1 and 2 10 kΩ or higher
      Auxiliary battery voltage is applied between terminals 1 and 2 Below 1 Ω
      Table 6. Text in Illustration
      *1 IGCT Relay

    3. Install the IGCT relay.


  7. Click here

    CHECK HARNESS AND CONNECTOR (HYBRID VEHICLE CONTROL ECU ASSEMBLY - NO. 2 ENGINE ROOM RELAY BLOCK)


    1. A0008OYE01

      Remove the PM IGCT fuse from the No. 2 engine room relay block.

      Table 7. Text in Illustration
      *1 No. 2 Engine Room Relay Block
      *2 PM IGCT Fuse

    2. Disconnect the A78 and A79 hybrid vehicle control ECU assembly connectors.

    3. A0006MKE02

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

      Table 8. Text in Illustration
      *1 No. 2 Engine Room Relay Block *2 PM IGCT Fuse
      *a

      Rear view of wire harness connector

      (to Hybrid Vehicle Control ECU Assembly)

      		 - -
      Standard Resistance
      Tester Connection Condition Specified Condition
      A79-4 (+B1) - 2 (PM IGCT fuse) Always Below 1 Ω
      A78-1 (+B2) - 2 (PM IGCT fuse) Always Below 1 Ω

    4. Install the PM IGCT fuse.

    5. Reconnect the A78 and A79 hybrid vehicle control ECU assembly connectors.


    • OKClick here
    • NG

      REPAIR OR REPLACE HARNESS OR CONNECTOR

  8. Click here

    CHECK HARNESS AND CONNECTOR (NO. 2 ENGINE ROOM RELAY BLOCK)


    1. A0006EFE02

      Remove the IGCT-MAIN fuse and PM IGCT fuse from the No. 2 engine room relay block.

      Table 9. Text in Illustration
      *1 No. 2 Engine Room Relay Block
      *2 PM IGCT Fuse
      *3 IGCT-MAIN Fuse

    2. Remove the IGCT relay from the No. 2 engine room relay block.

    3. A00058YE01

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      3 (IGCT relay) - 2 (IGCT-MAIN fuse) Always Below 1 Ω
      5 (IGCT relay) - 2 (PM IGCT fuse) Always Below 1 Ω
      Table 10. Text in Illustration
      *1 No. 2 Engine Room Relay Block
      *2 PM IGCT Fuse
      *3 IGCT Relay
      *4 IGCT-MAIN Fuse

    4. Install the IGCT-MAIN fuse and PM IGCT fuse.

    5. Install the IGCT relay.


    • OKClick here
    • NG

      REPAIR OR REPLACE HARNESS OR CONNECTOR

  9. Click here

    CHECK HARNESS AND CONNECTOR (HYBRID VEHICLE CONTROL ECU ASSEMBLY - NO. 2 ENGINE ROOM RELAY BLOCK)


    1. Remove the IGCT relay from the No. 2 engine room relay block.

    2. Disconnect the A79 hybrid vehicle control ECU assembly connector.

    3. A0005DIE02

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

      Table 11. Text in Illustration
      *1 No. 2 Engine Room Relay Block *2 IGCT Relay
      *a

      Rear view of wire harness connector

      (to Hybrid Vehicle Control ECU Assembly)

      		 - -
      Standard Resistance
      Tester Connection Condition Specified Condition
      A79-6 (MREL) - 1 (IGCT relay) Always Below 1 Ω
      A79-6 (MREL) or 1 (IGCT relay) - Body ground and other terminals Always 10 kΩ or higher

    4. Install the IGCT relay.

    5. Reconnect the A79 hybrid vehicle control ECU assembly connector.


    • OKClick here
    • NG

      REPAIR OR REPLACE HARNESS OR CONNECTOR

  10. Click here

    CHECK HARNESS AND CONNECTOR (NO. 2 ENGINE ROOM RELAY BLOCK - BODY GROUND)


    1. Remove the IGCT relay from the No. 2 engine room relay block.

    2. A0006X7E01

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      2 (IGCT relay) - Body ground Always Below 1 Ω
      Table 12. Text in Illustration
      *1 No. 2 Engine Room Relay Block
      *2 IGCT Relay

    3. Install the IGCT relay.


    • OKClick here
    • NG

      REPAIR OR REPLACE HARNESS OR CONNECTOR

  11. Click here

    CHECK HARNESS AND CONNECTOR (ENGINE ROOM RELAY BLOCK AND JUNCTION BLOCK ASSEMBLY - NO. 2 ENGINE ROOM RELAY BLOCK)


    1. Remove the IGCT-MAIN fuse from the No. 2 engine room relay block.

    2. Disconnect AMD terminal from the engine room relay block and junction block assembly.

    3. A0005QVE01

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

      Table 13. Text in Illustration
      *1 Engine Room Relay Block and Junction Block Assembly *2 No. 2 Engine Room Relay Block
      *3 IGCT-MAIN Fuse - -
      Standard Resistance
      Tester Connection Condition Specified Condition
      1K-1 (AMD) - 1 (IGCT-MAIN fuse) Always Below 1 Ω

    4. Install the IGCT-MAIN fuse.

    5. Connect AMD terminal.


  12. Click here

    CHECK FUSIBLE LINK BLOCK ASSEMBLY (R/B NO. 2)


    1. Check the fusible link block assembly (R/B NO. 2) 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. A0004DAE03

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      Fusible link block assembly 1 -2 terminals (R/B NO. 2) Always Below 1 Ω
      Table 14. Text in Illustration
      *1 Fusible Link Block Assembly

    4. Install the fusible link block assembly.


    • OK

      REPAIR OR REPLACE HARNESS OR CONNECTOR

    • NG

      REPLACE FUSIBLE LINK BLOCK ASSEMBLY (R/B NO. 2)

  13. Click here

    CHECK HARNESS AND CONNECTOR (HYBRID VEHICLE CONTROL ECU ASSEMBLY - NO. 2 ENGINE ROOM RELAY BLOCK)


    1. Disconnect the transmission control switch connector.

    2. A0008OYE01

      Remove the PM IGCT fuse from the No. 2 engine room relay block.

      Table 15. Text in Illustration
      *1 No. 2 Engine Room Relay Block
      *2 PM IGCT Fuse

    3. Disconnect the A78 and A79 hybrid vehicle control ECU assembly connectors.

    4. A0006MKE02

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

      Table 16. Text in Illustration
      *1 No. 2 Engine Room Relay Block *2 PM IGCT Fuse
      *a

      Rear view of wire harness connector

      (to Hybrid Vehicle Control ECU Assembly)

      		 - -
      Standard Resistance
      Tester Connection Condition Specified Condition
      A79-4 (+B1) or 2 (PM IGCT fuse) - Body ground and other terminals Always 10 kΩ or higher
      A78-1 (+B2) or 2 (PM IGCT fuse) - Body ground and other terminals Always 10 kΩ or higher

    5. Install the PM IGCT fuse.

    6. Reconnect the D10 shift lever position sensor connector.

    7. Reconnect the A78 and A79 hybrid vehicle control ECU assembly connectors.


  14. Click here

    REPAIR OR REPLACE HARNESS OR CONNECTOR


    • NEXT

      REPLACE FUSE (PM IGCT)

  15. Click here

    CHECK HARNESS AND CONNECTOR (NO. 2 ENGINE ROOM RELAY BLOCK)


    1. A0006EFE02

      Remove the IGCT-MAIN fuse and PM IGCT fuse from the No. 2 engine room relay block.

      Table 17. Text in Illustration
      *1 No. 2 Engine Room Relay Block
      *2 PM IGCT Fuse
      *3 IGCT-MAIN Fuse

    2. Remove the IGCT relay from the No. 2 engine room relay block.

    3. A00058YE01

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      3 (IGCT relay) or 2 (IGCT-MAIN fuse) - Body ground and other terminals Always 10 kΩ or higher
      5 (IGCT relay) or 2 (PM IGCT fuse) - Body ground and other terminals Always 10 kΩ or higher
      Table 18. Text in Illustration
      *1 No. 2 Engine Room Relay Block
      *2 PM IGCT Fuse
      *3 IGCT Relay
      *4 IGCT-MAIN Fuse

    4. Install the IGCT-MAIN fuse and PM IGCT fuse.

    5. Install the IGCT relay.


  16. Click here

    REPAIR OR REPLACE HARNESS OR CONNECTOR


    • NEXT

      REPLACE FUSE (IGCT-MAIN)