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DTC P179F-00: Gear Shift Actuator "B" Performance [11/2021 - ]: Procedure

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  1. CHECK VEHICLE CONDITION 
    1. Check for removal and installation history of the shift control actuator assembly (shift actuator ECU).

      HINT: 

      If the shift control actuator assembly (shift actuator ECU) has been replaced or removed, make sure to perform actuator position learning. Check for removal and installation history as this DTC may be stored if the learning has not been completed.

      Result

      Result Proceed to
      History exists A
      No history B

    Result: 

    B 

    See step  5

    Result: 

    A 

    See step  2

  2. CLEAR DTC 

    Pre-procedure1

    1. Turn the ignition switch to ON.

      Procedure1

    2. Clear the DTCs.

      Powertrain > Transmission > Clear DTCs 

      Result

      Proceed to
      NEXT

      Post-procedure1

    3. Turn the ignition switch off.
    4. Disconnect the GTS.
    5. 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. PERFORM UTILITY (ACT POSITION LEARNING) 

    Pre-procedure1

    1. Turn the ignition switch to ON.

      Procedure1

    2. Perform ACT Position Learning.

      HINT: 

      Refer to UTILITY [11/2021 - ]

      Powertrain > Transmission > Utility 

      Tester Display
      ACT Position Learning

      Result

      Proceed to
      NEXT

      Post-procedure1

    3. Turn the ignition switch off.

    Result: 

    NEXT 

    See step  4

  4. CHECK DTC OUTPUT 

    Pre-procedure1

    1. Start the engine.
    2. With the brake pedal depressed, perform a shift operation then change the shift state to N.
    3. With the brake pedal depressed, perform a shift operation then change the shift state to R.
    4. With the brake pedal depressed, perform a shift operation then change the shift state to D.
    5. Press the P position switch to change the shift state to P.

      Procedure1

    6. Check for DTCs.

      Powertrain > Transmission > Trouble Codes 

      Result

      Result Proceed to
      P179F-00 is not output A
      P179F-00 is output B

      Post-procedure1

    7. Turn the ignition switch off.

    Result: 

    A 

    END 

    Result: 

    B 

    See step  5

  5. CHECK DTC OUTPUT (TRANSMISSION) 

    Pre-procedure1

    1. Turn the ignition switch to ON.

      Procedure1

    2. Check if DTCs are output.

      Powertrain > Transmission > Trouble Codes 

      Result

      Result Proceed to
      No DTCs in the table below are output A
      P179F-00 and any DTCs in the table below are output B
      Relevant DTC
      P1790-14 Gear Shift Actuator "A" Supply Voltage "A" Circuit Short to Ground or Open
      P1796-14 Gear Shift Actuator "B" Supply Voltage "A" Circuit Short to Ground or Open
      U1176-87 Lost Communication with Gear Shift Control Module "A" (ch2) Missing Message
      U0291-00 Lost Communication with Gear Shift Control Module "B" (System 2) Missing Message
      P1789-00 Lost Communication with Gear Shift Control Module "A" from "B" (Sub CPU) Missing Message
      P1753-87 Lost Communication with Gear Shift Control Module "B" (Local-CAN) Missing Message
      U1170-00 Lost Communication with Brake System Control Module (Gear Shift Control Module "A")
      P179C-49 Gear Shift Actuator "A" Control Circuit Internal Electronic Failure
      P179D-49 Gear Shift Actuator "B" Control Circuit Internal Electronic Failure
      P18B2-00 Gear Shift Control Module "B" Motor Angle Sensor "A" Performance
      P18B6-00 Gear Shift Control Module "B" Motor Angle Sensor "B" Performance
      P18B5-62 Gear Shift Actuator "A" Phase U-V-W Current Sensor Signal Compare Failure
      P18B9-62 Gear Shift Actuator "B" Phase U-V-W Current Sensor Signal Compare Failure
      P0914-2B Gear Shift Position Circuit "A" Range/Performance Signal Cross Coupled
      P091A-2B Gear Shift Position Circuit "B" Range/Performance Signal Cross Coupled
      P1779-49 Gear Shift Control Module Backup Power Supply Internal Electronic Failure
      P1779-96 Gear Shift Control Module Backup Power Supply Component Internal Failure
      P177A-87 Lost Communication with Gear Shift Control Module Backup Power Supply Missing Message

      Post-procedure1

    3. Turn the ignition switch off.

    Result: 

    B 

    GO TO DTC CHART. Refer To  DIAGNOSTIC TROUBLE CODE CHART [11/2021 - ] 

    for Automatic Transaxle System: Refer to DIAGNOSTIC TROUBLE CODE CHART [11/2021 - 03/2024] , or refer to DIAGNOSTIC TROUBLE CODE CHART [03/2024 - ]

    for Electronic Shift Lever System: Refer to DIAGNOSTIC TROUBLE CODE CHART [11/2021 - ]

    Result: 

    A 

    See step  6

  6. INSPECT BATTERY TERMINAL (CONTACT PROBLEM) 
    1. Check the connection of the battery terminal.

      OK

      The battery is connected securely and there are no contact problems.

      HINT: 

      Perform an inspection with consideration of a power supply voltage interruption due to a loose terminal, poor connection, etc.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    CONNECT SECURELY 

    Result: 

    OK 

    See step  7

  7. CHECK HARNESS AND CONNECTOR (INTEGRATION CONTROL SUPPLY (INTEGRATED CAPACITOR) - SHIFT CONTROL ACTUATOR ASSEMBLY (SHIFT ACTUATOR ECU)) 

    Pre-procedure1

    1. Disconnect the B77 shift control actuator assembly (shift actuator ECU) connector.
    2. Turn the ignition switch to ON.

      Procedure1

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

      Standard Voltage

      Tester Connection Condition Specified Condition
      B77-8 (BUB1) - Body ground Ignition switch ON 8 to 14 V
      B77-6 (MA2) - Body ground Ignition switch ON 11 to 14 V

      Result

      Proceed to
      OK
      NG
      NOTE:

      As other DTCs will be stored when the ignition switch is turned to ON with the connector disconnected, be sure to clear the DTCs after the inspection.

      Post-procedure1

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

    Result: 

    NG 

    See step  9

    Result: 

    OK 

    See step  8

  8. INSPECT AUTOMATIC TRANSAXLE ASSEMBLY (STUCK/FREE SPINNING OFF PARKING LOCK SHAFT) 
    1. Check that the parking lock shaft.

      for UB80E: Refer to ON-VEHICLE INSPECTION [11/2021 - ]

      for UB80F: Refer to ON-VEHICLE INSPECTION [11/2021 - ]

      OK

      The parking lock shaft is not stuck, and moves reasonably smoothly to each shift position.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE SHIFT CONTROL ACTUATOR ASSEMBLY (SHIFT ACTUATOR ECU). Refer to  REMOVAL [11/2021 - ] 

    Result: 

    NG 

    REPLACE AUTOMATIC TRANSAXLE ASSEMBLY 

    for UB80E: Refer to REMOVAL [11/2021 - 03/2022] , or refer to REMOVAL [03/2022 - 03/2024] , or refer to REMOVAL [03/2024 - ]

    for UB80F: Refer to REMOVAL [11/2021 - 03/2022] , or refer to REMOVAL [03/2022 - 03/2024] , or refer to REMOVAL [03/2024 - ]

  9. CHECK HARNESS AND CONNECTOR (INTEGRATION CONTROL SUPPLY (INTEGRATED CAPACITOR) - SHIFT CONTROL ACTUATOR ASSEMBLY (SHIFT ACTUATOR ECU)) 

    Pre-procedure1

    1. Disconnect the B77 shift control actuator assembly (shift actuator ECU) connector.
    2. Disconnect the G102 integration control supply (integrated capacitor) connector.

      Procedure1

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

      Standard Resistance

      Tester Connection Condition Specified Condition
      B77-8 (BUB1) - G102-9 (BUAE) Always Below 1 Ω
      B77-6 (MA2) - G102-19 (BUA) Always Below 1 Ω
      B77-8 (BUB1) or G102-9 (BUAE) - Body ground and other terminals Always 10 kΩ or higher
      B77-6 (MA2) or G102-19 (BUA) - Body ground and other terminals Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

      Post-procedure1

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

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  10

  10. CHECK HARNESS AND CONNECTOR (SHIFT CONTROL ACTUATOR ASSEMBLY (SHIFT ACTUATOR ECU) - BODY GROUND) 

    Pre-procedure1

    1. Disconnect the B77 shift control actuator assembly (shift actuator ECU) connector.

      Procedure1

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

      Standard Resistance

      Tester Connection Condition Specified Condition
      B77-7 (E02) - Body ground Always Below 1 Ω

      Result

      Proceed to
      OK
      NG

      Post-procedure1

    3. Connect the shift control actuator assembly (shift actuator ECU) connector.

    Result: 

    OK 

    REPLACE SHIFT CONTROL ACTUATOR ASSEMBLY (SHIFT ACTUATOR ECU). Refer to  REMOVAL [11/2021 - ] 

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

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