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Home >> Lexus >> 2010 >> GS 450h >> Repair and Diagnosis (Single Page) >> Accessories & Equipment >> Anti-Theft Systems >> Smart Access System (Keyless Entry) (Diagnostics & Symptom Tests) >> Smart Access System With Push-Button Start >> Entry Functions do not Operate at All >> Procedure
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Entry Functions do not Operate at All: Procedure

  1. CHECK KEY CANCEL FUNCTION 
    1. Check that the key cancel function is set.

      OK

      Key cancel function is set.

    OK → END (UNSET KEY CANCEL FUNCTION) 

    NG: Go to next step 

  2. INSPECT FUSE (SECURITY, ECU-IG RH) 
    1. Remove the SECURITY and ECU-IG RH fuses from the main body ECU RH.
    2. Measure the resistance of the fuse.

      Standard resistance

      Below 1 Ω

    NG → REPLACE FUSE 

    OK: Go to next step 

  3. CHECK WIRE HARNESS (CERTIFICATION ECU - BATTERY AND BODY GROUND) 
    Fig 1: Identifying U28 ECU Connector Terminals
    GTY119982Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the U28 ECU connector.
    2. Measure the voltage and resistance of the wire harness side connector.

      Standard voltage

      Standard resistance 

      Tester Connection Condition Specified Condition
      U28-18 (IG) - Body ground Power switch OFF Below 1 V
      U28-18 (IG) - Body ground Power switch ON (IG) 10 to 14 V
      U28-1 (+B1) - Body ground Always 10 to 14 V
      Tester Connection Specified Condition
      U28-17 (E) - Body ground Below 1 Ω

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK → REPLACE CERTIFICATION ECU 

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