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DTC P1779-96: Gear Shift Control Module Backup Power Supply Component Internal Failure [10/2022 - ]: Procedure

  1. CHECK FREEZE FRAME DATA (GEAR SHIFT CONTROL MODULE BACKUP SIGNAL STATUS) 

    Pre-procedure1

    • Turn the ignition switch to ON.
    • Read the freeze frame data of DTC P1779-96.

      Powertrain > Hybrid Control > DTC(P1779-96) > Freeze Frame Data 

      Tester Display
      Gear Shift Control Module Backup Signal Status

      Result

      Result Proceed to
      The value of Gear Shift Control Module Backup Signal Status is not Capacitor External Failure A
      The value of Gear Shift Control Module Backup Signal Status is Capacitor External Failure B

    Post-procedure1

    • Turn the ignition switch off.

    Result: 

    B 

    See step  15

    Result: 

    A 

    See step  2

  2. CHECK FREEZE FRAME DATA (GEAR SHIFT CONTROL MODULE BACKUP SIGNAL STATUS) 

    Pre-procedure1

    • Turn the ignition switch to ON.
    • Read the freeze frame data of DTC P1779-96.

      Powertrain > Hybrid Control > DTC(P1779-96) > Freeze Frame Data 

      Tester Display
      Gear Shift Control Module Backup Signal Status

      Result

      Result Proceed to
      The value of Gear Shift Control Module Backup Signal Status is not Capacitor External Failure (Backup Possible) A
      The value of Gear Shift Control Module Backup Signal Status is Capacitor External Failure (Backup Possible) B

    Post-procedure1

    • Turn the ignition switch off.

    Result: 

    B 

    See step  9

    Result: 

    A 

    See step  3

  3. CHECK FREEZE FRAME DATA (GEAR SHIFT CONTROL MODULE BACKUP SIGNAL STATUS) 

    Pre-procedure1

    • Turn the ignition switch to ON.
    • Read the freeze frame data of DTC P1779-96.

      Powertrain > Hybrid Control > DTC(P1779-96) > Freeze Frame Data 

      Tester Display
      Gear Shift Control Module Backup Signal Status

      Result

      Result Proceed to
      The value of Gear Shift Control Module Backup Signal Status is not Capacitor External Failure (Brake Factor) A
      The value of Gear Shift Control Module Backup Signal Status is Capacitor External Failure (Brake Factor) B

    Post-procedure1

    • Turn the ignition switch off.

    Result: 

    B 

    See step  6

    Result: 

    A 

    See step  4

  4. CLEAR DTC 

    Pre-procedure1

    • Turn the ignition switch off and wait for 10 minutes or more.
    • Turn the ignition switch to ON.
    • Clear the DTCs.

      Powertrain > Hybrid Control > Clear DTCs 

      Result

      Proceed to
      NEXT

    Post-procedure1

    • Turn the ignition switch off.

    Result: 

    NEXT 

    See step  5

  5. CHECK DTC OUTPUT (PERFORM A REPRODUCTION TEST) 

    Pre-procedure1

    • Turn the ignition switch to ON and wait for 10 seconds or more.
    • Turn the ignition switch off and wait for 10 minutes or more.
    • Turn the ignition switch to ON.
    • Check for DTCs.

      Powertrain > Hybrid Control > Trouble Codes 

      Result

      Result Proceed to
      P1779-96 is output A
      P1779-96 is not output B

    Post-procedure1

    • Turn the ignition switch off.

    Result: 

    A 

    REPLACE INTEGRATION CONTROL SUPPLY (INTEGRATED CAPACITOR). Refer to  REMOVAL [10/2022 - 08/2023]  , or refer to  REMOVAL [08/2023 - ] 

    Result: 

    B 

    CHECK FOR INTERMITTENT PROBLEMS 

    Refer to HOW TO PROCEED WITH TROUBLESHOOTING [10/2022 - ]

    Refer to ELECTRONIC CIRCUIT INSPECTION PROCEDURE [10/2022 - ]

  6. CHECK HARNESS AND CONNECTOR (INTEGRATED CAPACITOR - BRAKE CONTROL POWER SUPPLY ASSEMBLY) 

    Pre-procedure1

    • Disconnect the H116 integration control supply (integrated capacitor) connector.
    • Disconnect the H159 brake control power supply assembly connector.
    • Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition Result
      H116-6 (BUA3) - H159-5 (SBIN) Always Below 1 Ω Ω
      H116-6 (BUA3) or H159-5 (SBIN) - Body ground and other terminals Always 10 kΩ or higher kΩ

      Result

      Proceed to
      OK
      NG

    Post-procedure1

    • Connect the brake control power supply assembly connector.
    • Connect the integration control supply (integrated capacitor) connector.

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  7

  7. CHECK HARNESS AND CONNECTOR (BRAKE CONTROL POWER SUPPLY ASSEMBLY - NO. 1 SKID CONTROL ECU) 

    Pre-procedure1

    • Disconnect the H159 brake control power supply assembly connectors.
    • Disconnect the A34 No. 1 skid control ECU (brake booster with master cylinder assembly) connector.
    • Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition Result
      H159-6 (OUT) - A34-2 (CBKP) Always Below 1 Ω Ω
      H159-6 (OUT) or A34-2 (CBKP) - Body ground and other terminals Always 10 kΩ or higher kΩ

      Result

      Proceed to
      OK
      NG

    Post-procedure1

    • Connect the No. 1 skid control ECU (brake booster with master cylinder assembly) connector.
    • Connect the brake control power supply assembly connectors.

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  8

  8. INSPECT BRAKE CONTROL POWER SUPPLY ASSEMBLY 
    1. Inspect the brake control power supply assembly.

      HINT: 

      Refer to PROCEDURE - Step 3

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE INTEGRATION CONTROL SUPPLY (INTEGRATED CAPACITOR). Refer to  REMOVAL [10/2022 - 08/2023]  , or refer to  REMOVAL [08/2023 - ] 

    Result: 

    NG 

    REPLACE BRAKE CONTROL POWER SUPPLY ASSEMBLY. Refer to  REMOVAL [10/2022 - ] 

  9. CHECK HARNESS AND CONNECTOR (INTEGRATED CAPACITOR - POWER DISTRIBUTION BOX ASSEMBLY) 

    Pre-procedure1

    • Disconnect the H116 integration control supply (integrated capacitor) connector.
    • Disconnect the C90 power distribution box assembly connector.
    • Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition Result
      H116-10 (BUE2) - C90-27 Always Below 1 Ω Ω
      H116-10 (BUE2) or C90-27 - Body ground and other terminals Always 10 kΩ or higher kΩ

      Result

      Proceed to
      OK
      NG

    Post-procedure1

    • Connect the power distribution box assembly connector.
    • Connect the integration control supply (integrated capacitor) connector.

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  10

  10. INSPECT POWER DISTRIBUTION BOX ASSEMBLY 

    Pre-procedure1

    • Measure the resistance according to the value(s) in the table below.
      GTY1124652Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Component without harness connected
      (Power Distribution Box Assembly)      		 - -

      Standard Resistance

      Tester Connection Condition Specified Condition Result
      C90-27 - z31-25 (SBAT) Always Below 1 Ω Ω
      C90-27 or z31-25 (SBAT) - Other terminals Always 10 kΩ or higher kΩ

      Result

      Proceed to
      OK
      NG

    Post-procedure1

    • Install the main body ECU (multiplex network body ECU) to the power distribution box assembly.

    Result: 

    NG 

    REPLACE POWER DISTRIBUTION BOX ASSEMBLY. Refer to  REMOVAL [10/2022 - 08/2023]  , or refer to  REMOVAL [08/2023 - ] 

    Result: 

    OK 

    See step  11

  11. CHECK HARNESS AND CONNECTOR (INTEGRATED CAPACITOR - FRONT DOOR LOCK WITH MOTOR ASSEMBLY LH) 

    Pre-procedure1

    • Disconnect the H116 integration control supply (integrated capacitor) connector.
    • Disconnect the D34 front door lock with motor assembly LH connector.
    • Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition Result
      H116-20 (BUA2) - D34-3 (BUB1) Always Below 1 Ω Ω
      H116-20 (BUA2) or D34-3 (BUB1) - Body ground and other terminals Always 10 kΩ or higher kΩ

      Result

      Proceed to
      OK
      NG

    Post-procedure1

    • Connect the front door lock with motor assembly LH connector.
    • Connect the integration control supply (integrated capacitor) connector.

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  12

  12. CHECK HARNESS AND CONNECTOR (INTEGRATED CAPACITOR - FRONT DOOR LOCK WITH MOTOR ASSEMBLY RH) 

    Pre-procedure1

    • Disconnect the H116 integration control supply (integrated capacitor) connector.
    • Disconnect the D15 front door lock with motor assembly RH connector.
    • Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition Result
      H116-20 (BUA2) - D15-3 (BUB2) Always Below 1 Ω Ω
      H116-20 (BUA2) or D15-3 (BUB2) - Body ground and other terminals Always 10 kΩ or higher kΩ

      Result

      Proceed to
      OK
      NG

    Post-procedure1

    • Connect the front door lock with motor assembly RH connector.
    • Connect the integration control supply (integrated capacitor) connector.

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  13

  13. CHECK HARNESS AND CONNECTOR (INTEGRATED CAPACITOR - REAR DOOR LOCK WITH MOTOR ASSEMBLY LH) 

    Pre-procedure1

    • Disconnect the H116 integration control supply (integrated capacitor) connector.
    • Disconnect the E16 rear door lock with motor assembly LH connector.
    • Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition Result
      H116-20 (BUA2) - E16-3 (BUB4) Always Below 1 Ω Ω
      H116-20 (BUA2) or E16-3 (BUB4) - Body ground and other terminals Always 10 kΩ or higher kΩ

      Result

      Proceed to
      OK
      NG

    Post-procedure1

    • Connect the rear door lock with motor assembly LH connector.
    • Connect the integration control supply (integrated capacitor) connector.

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  14

  14. CHECK HARNESS AND CONNECTOR (INTEGRATED CAPACITOR - REAR DOOR LOCK WITH MOTOR ASSEMBLY RH) 

    Pre-procedure1

    • Disconnect the H116 integration control supply (integrated capacitor) connector.
    • Disconnect the E6 rear door lock with motor assembly RH connector.
    • Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition Result
      H116-20 (BUA2) - E6-3 (BUB3) Always Below 1 Ω Ω
      H116-20 (BUA2) or E6-3 (BUB3) - Body ground and other terminals Always 10 kΩ or higher kΩ

      Result

      Proceed to
      OK
      NG

    Post-procedure1

    • Connect the rear door lock with motor assembly RH connector.
    • Connect the integration control supply (integrated capacitor) connector.

    Result: 

    OK 

    REPLACE INTEGRATION CONTROL SUPPLY (INTEGRATED CAPACITOR). Refer to  REMOVAL [10/2022 - 08/2023]  , or refer to  REMOVAL [08/2023 - ] 

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

  15. CHECK HARNESS AND CONNECTOR (BR TERMINAL INPUT VOLTAGE) 

    Pre-procedure1

    • Disconnect the H116 integration control supply (integrated capacitor) connector.
    • Turn the ignition switch to ON.
    • Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition Result
      H116-14 (BR) - Body ground Ignition switch to ON 8 to 14 V V

      Result

      Proceed to
      OK
      NG

    Post-procedure1

    • Turn the ignition switch off.
    • Connect the integration control supply (integrated capacitor) connector.

    Result: 

    NG 

    See step  18

    Result: 

    OK 

    See step  16

  16. CHECK HARNESS AND CONNECTOR (INTEGRATED CAPACITOR - SHIFT CONTROL ECU) 

    Pre-procedure1

    • Disconnect the H116 integration control supply (integrated capacitor) connector.
    • Disconnect the C35 transmission floor shift assembly (shift control ECU) connector.
    • Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition Result
      H116-1 (BUSE) - C35-13 (BUB) Always Below 1 Ω Ω
      H116-1 (BUSE) or C35-13 (BUB) - Body ground and other terminals Always 10 kΩ or higher kΩ

      Result

      Proceed to
      OK
      NG

    Post-procedure1

    • Connect the transmission floor shift assembly (shift control ECU) connector.
    • Connect the integration control supply (integrated capacitor) connector.

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  17

  17. CHECK HARNESS AND CONNECTOR (INTEGRATED CAPACITOR - SHIFT ACTUATOR ECU) 

    Pre-procedure1

    • Disconnect the H116 integration control supply (integrated capacitor) connector.
    • Disconnect the B56 shift control actuator assembly (shift actuator ECU) connector.
    • Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition Result
      H116-19 (BUA) - B56-6 (MA2) Always Below 1 Ω Ω
      H116-9 (BUAE) - B56-8 (BUB1) Always Below 1 Ω Ω
      H116-19 (BUA) or B56-6 (MA2) - Body ground and other terminals Always 10 kΩ or higher kΩ
      H116-9 (BUAE) or B56-8 (BUB1) - Body ground and other terminals Always 10 kΩ or higher kΩ

      Result

      Proceed to
      OK
      NG

    Post-procedure1

    • Connect the shift control actuator assembly (shift actuator ECU) connector.
    • Connect the integration control supply (integrated capacitor) connector.

    Result: 

    OK 

    REPLACE INTEGRATION CONTROL SUPPLY (INTEGRATED CAPACITOR). Refer to  REMOVAL [10/2022 - 08/2023]  , or refer to  REMOVAL [08/2023 - ] 

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

  18. CHECK HARNESS AND CONNECTOR (INTEGRATED CAPACITOR - SHIFT CONTROL ECU) 

    Pre-procedure1

    • Disconnect the H116 integration control supply (integrated capacitor) connector.
    • Disconnect the C35 transmission floor shift assembly (shift control ECU) connector.
    • Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition Result
      H116-14 (BR) - C35-20 (BUBO) Always Below 1 Ω Ω
      H116-14 (BR) or C35-20 (BUBO) - Body ground and other terminals Always 10 kΩ or higher kΩ

      Result

      Proceed to
      OK
      NG

    Post-procedure1

    • Connect the transmission floor shift assembly (shift control ECU) connector.
    • Connect the integration control supply (integrated capacitor) connector.

    Result: 

    OK 

    REPLACE TRANSMISSION FLOOR SHIFT ASSEMBLY (SHIFT CONTROL ECU). Refer to  REMOVAL [10/2022 - ] 

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

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