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Home >> Lexus >> 2024 >> LX 600 Base >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> Engine Control System (W/ Canister Pump Module) - Diagnostic Codes (9 Of 9), Circuit Tests & Symptom Tests (1 Of 2) >> SFI SYSTEM (w/ Canister Pump Module) >> Starter Signal Circuit [12/2021 - ] >> Procedure
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Starter Signal Circuit [12/2021 - ]: Procedure

  1. CHECK WHETHER ENGINE CAN BE CRANKED 
    1. Check if the engine can be cranked.

      Result

      Result Proceed to
      Engine cannot be cranked A
      Engine can be cranked B

    Result: 

    B 

    See step  19

    Result: 

    A 

    See step  2

  2. READ VALUE USING GTS (STARTER SW) 
    1. Check the value displayed on the GTS when the ignition switch is turned to ON and START positions.

      Powertrain > Engine > Data List 

      Tester Display
      Starter SW

      OK

      Condition GTS Display (Starter SW)
      Ignition switch ON OFF
      Engine started ON

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    See step  14

    Result: 

    OK 

    See step  3

  3. INSPECT ST NO. 1 RELAY 

    Refer to ON-VEHICLE INSPECTION [12/2021 - ]

    Result

    Proceed to
    OK
    NG

    Result: 

    NG 

    REPLACE ST NO. 1 RELAY 

    Result: 

    OK 

    See step  4

  4. INSPECT ST NO. 2 RELAY 

    Refer to ON-VEHICLE INSPECTION [12/2021 - ]

    Result

    Proceed to
    OK
    NG

    Result: 

    NG 

    REPLACE ST NO. 2 RELAY 

    Result: 

    OK 

    See step  5

  5. INSPECT STARTER ASSEMBLY 

    Refer to INSPECTION [12/2021 - ]

    Result

    Proceed to
    OK
    NG

    Result: 

    NG 

    REPLACE STARTER ASSEMBLY. Refer to  REMOVAL [12/2021 - ] 

    Result: 

    OK 

    See step  6

  6. CHECK HARNESS AND CONNECTOR (ST NO. 2 RELAY - STARTER ASSEMBLY) 
    1. Remove the ST NO. 2 relay from No. 2 engine room relay block and junction block assembly.
    2. Disconnect the starter assembly connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      3 (ST NO. 2 relay) - C52-1 (SL2) Always Below 1 Ω
      3 (ST NO. 2 relay) or C52-1 (SL2) - Body ground and other terminals Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  7

  7. CHECK HARNESS AND CONNECTOR (ST NO. 2 RELAY - ECM) 
    1. Remove the ST NO. 2 relay from the No. 2 engine room relay block and junction block assembly.
    2. Disconnect the ECM connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      2 (ST NO. 2 relay) - B70-34 (STA) Always Below 1 Ω

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  8

  8. CHECK HARNESS AND CONNECTOR (ST NO. 2 RELAY - BODY GROUND) 
    1. Remove the ST NO. 2 relay from the No. 2 engine room relay block and junction block assembly.
    2. Disconnect the ECM connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      1 (ST NO. 2 relay) - Body ground Always Below 1 Ω

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  9

  9. CHECK TERMINAL VOLTAGE (POWER SOURCE OF ST NO. 2 RELAY) 
    GTY1074526Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    *1 No. 2 Engine Room Relay Block and Junction Block Assembly
    *2 ST NO. 2 Relay
    1. Remove the ST NO. 2 relay from the No. 2 engine room relay block and junction block assembly.
    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      5 (ST NO. 2 relay) - Body ground Always 11 to 14 V

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  10

  10. CHECK HARNESS AND CONNECTOR (ST NO. 1 RELAY - STARTER ASSEMBLY) 
    1. Remove the ST NO. 1 relay from No. 2 engine room relay block and junction block assembly.
    2. Disconnect the starter assembly connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      3 (ST NO. 1 relay) - C52-2 (SL1) Always Below 1 Ω
      3 (ST NO. 1 relay) or C52-2 (SL1) - Body ground and other terminals Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR (BATTERY - ST NO. 2 RELAY) 

    Result: 

    OK 

    See step  11

  11. CHECK HARNESS AND CONNECTOR (ST NO. 1 RELAY - BODY GROUND) 
    1. Remove the ST NO. 1 relay from No. 2 engine room relay block and junction block assembly.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      1 (ST NO. 1 relay) - Body ground Always Below 1 Ω

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  12

  12. CHECK TERMINAL VOLTAGE (POWER SOURCE OF ST NO. 1 RELAY) 
    GTY1074741Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    *1 No. 2 Engine Room Relay Block and Junction Block Assembly
    *2 ST NO. 1 Relay
    1. Remove the ST NO. 1 relay from the No. 2 engine room relay block and junction block assembly.
    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      5 (ST NO. 1 relay) - Body ground Always 11 to 14 V

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR (BATTERY - ST NO. 1 RELAY) 

    Result: 

    OK 

    See step  13

  13. CHECK HARNESS AND CONNECTOR (PARK/NEUTRAL POSITION SWITCH ASSEMBLY - ST NO. 1 RELAY) 
    1. Disconnect the park/neutral position switch assembly connector.
    2. Remove the ST NO. 1 relay from No. 2 engine room relay block and junction block assembly.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      C34-5 (L) - 2 (ST NO. 1 relay) Always Below 1 Ω

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPAIR OR REPLACE HARNESS OR CONNECTOR (BATTERY - STARTER ASSEMBLY) 

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

  14. CHECK STOP AND START SYSTEM 

    Refer to HOW TO PROCEED WITH TROUBLESHOOTING [12/2021 - ]

    Result

    Proceed to
    OK
    NG

    Result: 

    NG 

    REPAIR STOP AND START SYSTEM 

    Result: 

    OK 

    See step  15

  15. CHECK HARNESS AND CONNECTOR (ENGINE STOP AND START ECU - ECM - ST NO. 2 RELAY) 
    1. Disconnect the engine stop and start ECU connector.
    2. Disconnect the ECM connector.
    3. Remove the ST NO. 2 relay from the No. 2 engine room relay block and junction block assembly.
    4. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      B38-23 (STA2) - B70-34 (STA) Always Below 1 Ω
      B38-23 (STA2), B70-34 (STA) or 2 (ST NO. 2 relay) - Body ground Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  16

  16. INSPECT PARK/NEUTRAL POSITION SWITCH ASSEMBLY 

    Refer to INSPECTION [12/2021 - ]

    Result

    Proceed to
    OK
    NG

    Result: 

    NG 

    REPLACE PARK/NEUTRAL POSITION SWITCH ASSEMBLY. Refer to  REMOVAL [12/2021 - ] 

    Result: 

    OK 

    See step  17

  17. CHECK HARNESS AND CONNECTOR (PARK/NEUTRAL POSITION SWITCH ASSEMBLY - ENGINE STOP AND START ECU - ST NO. 1 RELAY - CERTIFICATION ECU) 
    1. Disconnect the park/neutral position switch assembly connector.
    2. Disconnect the engine stop and start ECU connector.
    3. Remove the ST NO. 1 relay from the No. 2 engine room relay block and junction block assembly.
    4. Disconnect the certification ECU (smart key ECU assembly) connector.
    5. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      C34-5 (L) - B38-21 (STA) Always Below 1 Ω
      C34-5 (L) - I40-3 (STA) Always Below 1 Ω
      C34-5 (L), B38-21 (STA), 2 (ST NO. 1 relay) or I40-3 (STA) - Body ground Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  18

  18. CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU - PARK/NEUTRAL POSITION SWITCH ASSEMBLY - ECM - ENGINE STOP AND START ECU) 
    1. Disconnect the certification ECU (smart key ECU assembly) connector.
    2. Disconnect the park/neutral position switch assembly connector.
    3. Disconnect the ECM connector.
    4. Disconnect the engine stop and start ECU connector.
    5. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      I40-10 (STAR) - C34-4 (B) Always Below 1 Ω
      I40-10 (STAR) - C37-7 (NSW) Always Below 1 Ω
      I40-10 (STAR) - B38-17 (CLL) Always Below 1 Ω
      I40-10 (STAR), C34-4 (B), C37-7 (NSW) or B38-17 (CLL) - Body ground Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    GO TO SMART ACCESS SYSTEM WITH PUSH-BUTTON START. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [12/2021 - ] 

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

  19. READ VALUE USING GTS (STARTER SW) 
    1. Check the value displayed on the GTS when the ignition switch is turned to ON and START positions.

      Powertrain > Engine > Data List 

      Tester Display
      Starter SW

      OK

      Condition GTS Display (Starter SW)
      Ignition switch ON OFF
      Engine started ON

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE. Refer to  PROBLEM SYMPTOMS TABLE [12/2021 - ] 

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR (ST RELAY - ECM) 

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