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DTC P178A-14: Gear Shift Control Module "B" Wake-up Circuit Short to Ground or Open [10/2022 - ]: Procedure

  1. CHECK HARNESS AND CONNECTOR (WAKE TERMINAL VOLTAGE) 

    Pre-procedure1

    • Disconnect the B57 shift control actuator assembly (shift actuator ECU) connector.
    • Turn the ignition switch to ON.
      NOTE:

      Turning the ignition switch to ON with the connector disconnected causes other DTCs to be stored. Clear the DTCs after performing this inspection.

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

      Standard Voltage

      Tester Connection Condition Specified Condition Result
      B57-5 (WAKE) - Body ground Ignition switch ON 11 to 14 V V

      Result

      Proceed to
      OK
      NG

    Post-procedure1

    • Turn the ignition switch off.
    • Connect the shift control actuator assembly (shift actuator ECU) connector.

    Result: 

    OK 

    REPLACE SHIFT CONTROL ACTUATOR ASSEMBLY (SHIFT ACTUATOR ECU). Refer to  REMOVAL [10/2022 - 08/2023]  , or refer to  REMOVAL [08/2023 - ] 

    Result: 

    NG 

    See step  2

  2. CHECK HARNESS AND CONNECTOR (SHIFT ACTUATOR ECU - SHIFT CONTROL ECU) 

    Pre-procedure1

    • Disconnect the B57 shift control actuator assembly (shift actuator ECU) 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
      B57-5 (WAKE) - C35-5 (WAKE) Always Below 1 Ω Ω
      B57-5 (WAKE) or C35-5 (WAKE) - Body ground and other terminals Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Post-procedure1

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

    Result: 

    OK 

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

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR