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DTC P178A-14: Gear Shift Control Module "B" Wake-up Circuit Short to Ground or Open [12/2022 - ]: Procedure

  1. CHECK HARNESS AND CONNECTOR (WAKE TERMINAL VOLTAGE) 

    Pre-procedure1

    • Disconnect the C50 shift actuator ECU (shift control actuator assembly) 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
      C50-5 (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 actuator ECU (shift control actuator assembly) connector.

    Result: 

    OK 

    REPLACE SHIFT ACTUATOR ECU (SHIFT CONTROL ACTUATOR ASSSEMBLY). Refer to  REMOVAL [12/2022 - ] 

    Result: 

    NG 

    See step  2

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

    Pre-procedure1

    • Disconnect the C50 shift actuator ECU (shift control actuator assembly) connector.
    • Disconnect the K53 shift control ECU (transmission floor shift assembly) connector.
    • Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition Result
      C50-5 (WAKE) - K53-5 (WAKE) Always Below 1 Ω Ω
      C50-5 (WAKE) or K53-5 (WAKE) - Body ground and other terminals Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Post-procedure1

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

    Result: 

    OK 

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

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR