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DTC P176D-12: IG2 Signal (Gear Shift Control Module "A") Circuit Short to Auxiliary Battery [12/2022 - ]: Procedure

  1. CHECK SHIFT CONTROL ECU (TRANSMISSION FLOOR SHIFT ASSEMBLY) (IGP TERMINAL VOLTAGE) 

    Pre-procedure1

    • Disconnect the K53 shift control ECU (transmission floor shift assembly) connector.
    • Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition Result
      K53-1 (IGP) - Body ground Ignition switch off Below 1 V V

      Result

      Proceed to
      OK
      NG

    Post-procedure1

    • Connect the shift control ECU (transmission floor shift assembly) connector.

    Result: 

    NG 

    See step  4

    Result: 

    OK 

    See step  2

  2. CLEAR DTC 

    Pre-procedure1

    • 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.
    • Disconnect the GTS.
    • Leave the vehicle as is for 60 seconds or more.
      NOTE:
      • Do not connect the GTS.
      • Do not depress the brake pedal.
      • Do not open/close any of the doors.

    Result: 

    NEXT 

    See step  3

  3. CHECK DTC OUTPUT (PERFORM A REPRODUCTION TEST) 

    Pre-procedure1

    • Turn the ignition switch to ON and wait for 1 minute or more.
    • Turn the ignition switch to OFF and wait for 1 minute or more.
    • Turn the ignition switch to ON.
    • Check for DTCs.

      Powertrain > Hybrid Control > Trouble Codes 

      Result

      Result Proceed to
      P176D-12 is not output A
      P176D-12 is output B

    Post-procedure1

    • Turn the ignition switch off.

    Result: 

    A 

    END 

    Result: 

    B 

    REPLACE SHIFT CONTROL ECU (TRANSMISSION FLOOR SHIFT ASSEMBLY). Refer to  REMOVAL [12/2022 - ] 

  4. CHECK HARNESS AND CONNECTOR (SHIFT CONTROL ECU - IGP RELAY) 

    Pre-procedure1

    • Disconnect the K53 shift control ECU (transmission floor shift assembly) connector.
    • Remove the IGP relay from the No. 1 engine room relay block and No. 1 junction block assembly.
    • Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition Result
      K53-1 (IGP) - Body ground Ignition switch off Below 1 V V

      Result

      Proceed to
      OK
      NG

    Post-procedure1

    • Install the IGP relay to the No. 1 engine room relay block and No. 1 junction block assembly.
    • Connect the shift control ECU (transmission floor shift assembly) connector.

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  5

  5. INSPECT RELAY (IGP) 

    Pre-procedure1

    • Remove the IGP relay from the No. 1 engine room relay block and No. 1 junction block assembly.
    • Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition Result
      3 - 5 Battery voltage not applied between terminals 1 and 2 10 kΩ or higher kΩ
      3 - 5 Battery voltage applied between terminals 1 and 2 Below 1 Ω Ω

      Result

      Proceed to
      OK
      NG
      GTY447534Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    Post-procedure1

    • Install the IGP relay to the No. 1 engine room relay block and No. 1 junction block assembly.

    Result: 

    NG 

    REPLACE RELAY (IGP) 

    Result: 

    OK 

    See step  6

  6. INSPECT CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) 

    Pre-procedure1

    • None
    • Measure the voltage according to the value(s) in the table below.
      Tester Connection Condition Specified Condition Result
      K23-24 (IGPD) - Body ground Ignition switch off Below 1 V V

      Result

      Proceed to
      OK
      NG

    Post-procedure1

    • None

    Result: 

    OK 

    CHECK FOR INTERMITTENT PROBLEMS 

    Refer to HOW TO PROCEED WITH TROUBLESHOOTING [12/2022 - ]

    Refer to ELECTRONIC CIRCUIT INSPECTION PROCEDURE [12/2022 - ]

    Result: 

    NG 

    See step  7

  7. CHECK HARNESS AND CONNECTOR (IGP RELAY - CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)) 

    Pre-procedure1

    • Remove the IGP relay from the No. 1 engine room relay block and No. 1 junction block assembly.
    • Disconnect the K23 certification ECU (smart key ECU Assembly) connector.
    • Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition Result
      K23-24 (IGPD) - Body ground Ignition switch off Below 1 V V

      Result

      Proceed to
      OK
      NG

    Post-procedure1

    • Connect the certification ECU (smart key ECU Assembly) connector.
    • Install the IGP relay to the No. 1 engine room relay block and No. 1 junction block assembly.

    Result: 

    OK 

    CHECK SMART KEY SYSTEM (FOR START FUNCTION). Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [12/2022 - ] 

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

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