LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Lexus >> 2019 >> LS 500 Base, AWD >> Repair and Diagnosis (Single Page) >> Transmission >> Transmission Control Systems >> Electronic A/T Shift Lever System (Aga0F) - Diagnostic Codes (2 Of 5) >> Electronic Shift Lever System >> DTC P176D-12: IG2 Signal (Gear Shift Control Module "A") Circuit Short to Battery [12/2017 - 10/2023] >> Procedure
April 5, 2026: LEMON Manuals is launched! Read the announcement.

DTC P176D-12: IG2 Signal (Gear Shift Control Module "A") Circuit Short to Battery [12/2017 - 10/2023]: Procedure

  1. CHECK CONNECTOR CONNECTION CONDITION (SHIFT CONTROL ECU CONNECTOR) 
    1. Check the connector connections and contact pressure of the relevant terminals for the shift control ECU connectors.
      GTY799322Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Refer to ELECTRONIC CIRCUIT INSPECTION PROCEDURE [12/2017 - ]

      OK

      The connectors are connected securely and there are no contact pressure problems.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    CONNECT SECURELY 

    Result: 

    OK 

    See step  2

  2. CHECK SHIFT CONTROL ECU 
    1. Disconnect the G81 shift control ECU connector.
    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Switch Condition Specified Condition
      G81-27 (IG2) - Body ground Engine switch off → Engine switch on (IG) 1 V or less → 8 V or higher
      NOTE:

      Turning the engine switch on (IG) with the connector disconnected causes other DTCs to be stored. Clear the DTCs after performing this inspection.

    3. Turn the engine switch off.
    4. Reconnect the G81 shift control ECU connector.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    See step  5

    Result: 

    OK 

    See step  3

  3. CLEAR DTC 
    1. Connect the Techstream to the DLC3.
    2. Turn the engine switch on (IG).
    3. Enter the following menus: Powertrain / Transmission / Trouble Codes.

      Powertrain > Transmission > Trouble Codes 

    4. Check for DTCs and freeze frame data and then write them down.
    5. Clear the DTCs.

      Powertrain > Transmission > Clear DTCs 

    6. Turn the engine switch off.
    7. Disconnect the Techstream from the DLC3.
    8. Leave the vehicle as is for 60 seconds or more.
      NOTE:
      • Do not connect the Techstream.
      • Do not depress brake pedal.
      • Do not open/close any of the doors.

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  4

  4. CHECK DTC OUTPUT (SIMULATION TEST) 
    1. Turn the engine switch on (IG) and wait for 15 seconds or more.
    2. Turn the engine switch off and wait for 2 minutes or more.
    3. Connect the Techstream to the DLC3.
    4. Turn the engine switch on (IG).
    5. Enter the following menus: Powertrain / Transmission / Trouble Codes.

      Powertrain > Transmission > Trouble Codes 

    6. Check if DTCs are output.

      Result

      Result  Proceed to
      P176D-12 is not output. A
      P176D-12 is output. B
    7. Turn the engine switch off.

    Result: 

    A 

    END 

    Result: 

    B 

    REPLACE SHIFT CONTROL ECU. Refer to  REMOVAL [12/2017 - 09/2018]  , or refer to  REMOVAL [09/2018 - 10/2020]  , or refer to  REMOVAL [10/2020 - 10/2022]  , or refer to  REMOVAL [10/2022 - 10/2023] 

  5. CHECK HARNESS AND CONNECTOR (SHIFT CONTROL ECU - PASSENGER SIDE JUNCTION BLOCK ASSEMBLY (IG2 P RELAY)) 
    1. Disconnect the G81 shift control ECU connector.
    2. Disconnect the 4D passenger side junction block assembly connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance (Check for Short)

      Tester Connection Condition Specified Condition
      G81-27 (IG2) or 4D-29 - Body ground and other terminals Always 10 kΩ or higher
    4. Reconnect the 4D passenger side junction block assembly connector.
    5. Reconnect the G81 shift control ECU connector.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  6

  6. INSPECT PASSENGER SIDE JUNCTION BLOCK ASSEMBLY (IG2 P RELAY) 
    1. Disconnect the passenger side junction block assembly connectors.
      GTY799053Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *1 Passenger Side Junction Block Assembly - -
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance (Check for Short)

      Tester Connection Condition Specified Condition
      4L-1 - 4D-29 Always 10 kΩ or higher
    3. Reconnect the passenger side junction block assembly connectors.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPLACE PASSENGER SIDE JUNCTION BLOCK ASSEMBLY. Refer to  REMOVAL [12/2017 - 10/2023] 

    Result: 

    OK 

    See step  7

  7. CHECK CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) 
    1. Measure the voltage according to the value(s) in the table below.
      GTY792730Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Component with harness connected
      (Certification ECU (Smart Key ECU Assembly))

      Standard Voltage

      Tester Connection Switch Condition Specified Condition
      G71-17 (IG1D) - Body ground Engine switch off → Engine switch on (IG) 1 V or less → 9 V or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    CHECK FOR INTERMITTENT PROBLEMS. Refer to  ELECTRONIC CIRCUIT INSPECTION PROCEDURE [12/2017 - ] 

    Result: 

    NG 

    See step  8

  8. CHECK HARNESS AND CONNECTOR (PASSENGER SIDE JUNCTION BLOCK ASSEMBLY (IG2 P RELAY) - CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)) 
    1. Disconnect the G71 certification ECU (smart key ECU assembly) connector.
    2. Disconnect the 4D passenger side junction block assembly connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance (Check for Short)

      Tester Connection Condition Specified Condition
      G71-17 (IG1D) or 4D-20 - Body ground and other terminals Always 10 kΩ or higher
    4. Reconnect the 4D passenger side junction block assembly connector.
    5. Reconnect the G71 certification ECU (smart key ECU assembly) connector.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    CHECK SMART ACCESS SYSTEM WITH PUSH-BUTTON START. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [12/2017 - 10/2022]  , or refer to  HOW TO PROCEED WITH TROUBLESHOOTING [10/2022 - 10/2023] 

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

scientia non olet · About LEMON Manuals