LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Lexus >> 2019 >> GS 350 Base, AWD >> Repair and Diagnosis (Single Page) >> Accessories & Equipment >> Anti-Theft Systems >> Smart Access System (Keyless Start) (Diagnostic Codes & Symptom Tests) >> SMART ACCESS SYSTEM WITH PUSH-BUTTON START(for Start Function) >> Symptom Tests >> Power Source Mode does not Change to ON (IG) [09/2014 - 10/2015] >> Procedure
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Power Source Mode does not Change to ON (IG) [09/2014 - 10/2015]: Procedure

  1. CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) - NO. 1 INTEGRATION RELAY) 
    1. Disconnect the A34 connectors from the certification ECU (smart key ECU assembly).
    2. Disconnect the 2E and 2F connectors from the No. 1 integration relay.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      A34-9 (IG2D) - 2E-2 Always Below 1 Ω
      2F-1 - Body ground
      A34-9 (IG2D) - 2E-2 - Body ground 10 kΩ or higher

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  2

  2. INSPECT NO. 1 INTEGRATION RELAY (IG2 RELAY) 
    1. Remove the No. 1 integration relay.
      GTY645609Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      2F-6 - 2D-1 Battery voltage not applied to terminals 2E-2 and 2F-1 10 kΩ or higher
      Battery voltage applied to terminals 2E-2 and 2F-1 Below 1 Ω
      TEXT IN ILLUSTRATION

      *a Component without harness connected
      (No. 1 Integration Relay)

    Result: 

    NG 

    REPLACE NO. 1 INTEGRATION RELAY 

    Result: 

    OK 

    See step  3

  3. CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) - COWL SIDE JUNCTION BLOCK RH) 
    1. Disconnect the N93 connector from the certification ECU (smart key ECU assembly).
    2. Disconnect the 4A connector from the connector from the cowl side junction block RH.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      N93-6 (IG1D) - 4A-25 Always Below 1 Ω
      4A-4 - Body ground
      N93-6 (IG1D) and 4A-25 - Body ground 10 kΩ or higher

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  4

  4. CHECK HARNESS AND CONNECTOR (COWL SIDE JUNCTION BLOCK RH - COWL SIDE JUNCTION BLOCK LH) 
    1. Disconnect the 4A connector from the cowl side junction block RHr.
    2. Disconnect the 5A and 5B connectors from the cowl side junction block LH.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      4A-40 - 5A-35 Always Below 1 Ω
      5B-1 - Body ground
      4A-40 and 5A-35 - Body ground 10 kΩ or higher

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  5

  5. CHECK HARNESS AND CONNECTOR (COWL SIDE JUNCTION BLOCK LH - NO. 1 JUNCTION BLOCK ASSEMBLY) 
    1. Disconnect the 5C connector from the cowl side junction block LH.
    2. Disconnect the 6B and 6A connectors from the No. 1 junction block assembly.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      5C-13 - 6B-8 Always Below 1 Ω
      6A-9 - Body ground
      5C-13 and 6B-8 - Body ground 10 kΩ or higher

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  6

  6. INSPECT COWL SIDE JUNCTION BLOCK RH (RH-IG1 RLY1, RH-IG1 RLY2 RELAY) 
    1. Remove the cowl side junction block RH.
    2. Measure the resistance according to the value(s) in the table below.
      GTY670354Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      TEXT IN ILLUSTRATION

      *a Component without harness connected
      (cowl side junction block RH)      		 - -

      Standard Resistance

      Tester Connection Condition Specified Condition
      4E-1 - 4D-4 Battery voltage not applied to terminals 4A-25 and 4A-4 10 kΩ or higher
      Battery voltage applied to terminals 4A-25 and 4A-4 Below 1 Ω
      4E-1 - 4A-6 Battery voltage not applied to terminals 4A-25 and 4A-4 10 kΩ or higher
      Battery voltage applied to terminals 4A-25 and 4A-4 Below 1 Ω

    Result: 

    NG 

    REPLACE COWL SIDE JUNCTION BLOCK RH 

    Result: 

    OK 

    See step  7

  7. INSPECT COWL SIDE JUNCTION BLOCK LH (LH-IG1 RLY1, LH-IG1 RLY2 RELAY) 
    1. Remove the cowl side junction block LH (Refer to REMOVAL [09/2014 - ] ).
    2. Measure the resistance according to the value(s) in the table below.
      GTY630382Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      TEXT IN ILLUSTRATION

      *a Component without harness connected
      (cowl side junction block LH)      		 - -

      Standard Resistance

      Tester Connection Condition Specified Condition
      5E-1 - 5B-7 Battery voltage not applied to terminals 5A-35 and 5B-1 10 kΩ or higher
      Battery voltage applied to terminals 5A-35 and 5B-1 Below 1 Ω
      5E-1 - 5D-3 Battery voltage not applied to terminals 5A-35 and 5B-1 10 kΩ or higher
      Battery voltage applied to terminals 5A-35 and 5B-1 Below 1 Ω

    Result: 

    NG 

    REPLACE MAIN BODY ECU (COWL SIDE JUNCTION BLOCK LH) 

    (Refer to REMOVAL [09/2014 - ] )

    Result: 

    OK 

    See step  8

  8. INSPECT NO. 1 JUNCTION BLOCK ASSEMBLY (RR-IG1 RLY1, RR-IG1 RLY2 RELAY) 
    1. Remove the No. 1 junction block assembly.
    2. Measure the resistance according to the value(s) in the table below.
      GTY634580Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      TEXT IN ILLUSTRATION

      *a Component without harness connected
      (No. 1 junction block assembly)      		 - -

      Standard Resistance

      Tester Connection Condition Specified Condition
      6D-1 - 6B-14 Battery voltage not applied to terminals 6B-8 and 6A-9 10 kΩ or higher
      Battery voltage applied to terminals 6B-8 and 6A-9 Below 1 Ω
      6D-1 - 6A-8 Battery voltage not applied to terminals 6B-14 and 6A-9 10 kΩ or higher
      Battery voltage applied to terminals 6B-14 and 6A-9 Below 1 Ω

    Result: 

    NG 

    REPLACE NO. 1 JUNCTION BLOCK ASSEMBLY 

    Result: 

    OK 

    See step  9

  9. CHECK CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) 
    1. Measure the voltage according to the value(s) in the table below.
      GTY667593Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      TEXT IN ILLUSTRATION

      *a Component with harness connected
      (Certification ECU (Smart Key ECU Assembly))      		 - -

      Standard Voltage

      Tester Connection Condition Specified Condition
      A34-9 (IG2D) - Body ground Engine switch on (ACC) → Engine switch on (IG) 1 V or less → 9 V or higher
      N93-6 (IG1D) - Body ground Engine switch on (ACC) → Engine switch on (IG) 1 V or less → 9 V or higher

    Result: 

    OK 

    CHECK RELAY CONTACT SIDE CIRCUIT 

    (Refer to HOW TO PROCEED WITH TROUBLESHOOTING [09/2014 - 10/2015] )

    Result: 

    NG 

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) 

    (Refer to REMOVAL [09/2014 - ] )

scientia non olet · About LEMON Manuals