LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Lexus >> 2017 >> RC 300 Base >> Repair and Diagnosis >> Body & Frame >> Door Locks >> Smart Access System (For Start) - Symptom Tests >> SMART ACCESS SYSTEM WITH PUSH-BUTTON START (for Start Function) >> Power Source Mode does not Change to ON (ACC) [09/2014 - ] >> Procedure
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Power Source Mode does not Change to ON (ACC) [09/2014 - ]: Procedure

  1. CHECK FOR DTC 
    1. Using the Techstream, check for certification ECU (smart key ECU assembly) DTCs.

      Body Electrical > Power Source Control > Trouble Codes 

      Body Electrical > Smart Access > Trouble Codes 

      Body Electrical > Starting Control > Trouble Codes 

      Result

      Result Proceed to
      DTCs are not output A
      Smart access system with push-button start (for Start Function) DTCs are output B

    Result: 

    GO TO DIAGNOSTIC TROUBLE CODE CHART. Refer to  DIAGNOSTIC TROUBLE CODE CHART [09/2014 - 10/2015]  , or refer to  DIAGNOSTIC TROUBLE CODE CHART [10/2015 - 11/2017]  , or refer to  DIAGNOSTIC TROUBLE CODE CHART [11/2017 - 11/2019]  , or refer to  DIAGNOSTIC TROUBLE CODE CHART [11/2019 - 10/2022]  , or refer to  DIAGNOSTIC TROUBLE CODE CHART [10/2022 - ] 

    Result: 

    See step  2

  2. CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) - INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY) 

    Refer to PROCEDURE - Step 3

    Result

    Proceed to
    OK
    NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  3

  3. INSPECT INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY (ACC RELAY) 

    Refer to PROCEDURE - Step 4

    Result

    Proceed to
    OK
    NG

    Result: 

    NG 

    REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY. Refer to  REMOVAL [09/2014 - ] 

    Result: 

    OK 

    See step  4

  4. CHECK SMART KEY ECU ASSEMBLY 

    Refer to PROCEDURE - Step 5

    Result

    Proceed to
    OK
    NG

    Result: 

    OK 

    USE SIMULATION METHOD TO CHECK. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [09/2014 - 10/2015]  , or refer to  HOW TO PROCEED WITH TROUBLESHOOTING [10/2015 - 11/2017]  , or refer to  HOW TO PROCEED WITH TROUBLESHOOTING [11/2017 - 10/2018]  , or refer to  HOW TO PROCEED WITH TROUBLESHOOTING [10/2018 - 11/2019]  , or refer to  HOW TO PROCEED WITH TROUBLESHOOTING [11/2019 - 09/2020]  , or refer to  HOW TO PROCEED WITH TROUBLESHOOTING [09/2020 - 10/2022]  , or refer to  HOW TO PROCEED WITH TROUBLESHOOTING [10/2022 - ] 

    Result: 

    NG 

    REPLACE SMART KEY ECU ASSEMBLY. Refer to  REMOVAL [09/2014 - ]