LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Lexus >> 2007 >> IS 250 AWD >> Repair and Diagnosis >> Engine Mechanical >> Starter >> Starting (4GR-FSE) >> Smart Access System With Push-Button Start >> Engine Does Not Start >> Inspection Procedure
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Inspection Procedure

  1. CHECK FOR DTC 
    1. Delete the DTCs (See DTC CHECK/CLEAR  ).

      HINT:

      After all the DTCs are cleared, check if the trouble occurs again 5 seconds after the engine switch is turned on (IG).

    2. Check for DTCs again.

      OK: 

      No DTC is output. 

    NG: GO TO  DIAGNOSTIC TROUBLE CODE TABLE  

    OK: Go To Next Step 

  2. CHECK BASIC FUNCTION 
    1. Check the engine start function.
      1. A/T Models: When there is fuel in the fuel tank, the key is inside the vehicle and the shift lever is in P, check that depressing the brake pedal causes the engine to start.
      2. M/T Models: When there is fuel in the tank, the key is inside the vehicle, check that depressing the clutch pedal and the brake pedal causes the engine to start.

        OK: 

        Engine starts. 

    NG: Go to step   3 

    OK: 

    END 

  3. CHECK SWITCH CONDITION 
    1. Check the engine switch condition.
      1. A/T Models: When the key is inside the vehicle and the shift lever is in P, check that pressing the engine switch causes the power source mode to change as follows.
      2. M/T Models: When the key is inside the vehicle, check the brake pedal causes the engine to start.

        OK: 

        off --> on (ACC) --> on (IG) --> off 

    NG: GO TO  POWER SOURCE MODE DOES NOT CHANGE  

    OK: Go To Next Step 

  4. CHECK BASIC FUNCTION 
    1. Check the engine cranking function.
      1. A/T Models: When there is fuel in the fuel tank, the key is inside the vehicle and the shift lever is in P, check that depressing the brake pedal and pressing the engine switch cranks the engine.
      2. M/T Models: When there is fuel in the tank, the key is inside the vehicle, check that depressing the clutch pedal and the brake pedal and pressing the engine switch cranks the engine.

        OK: 

        Engine cranks. 

    NG: Go to step   5 

    OK: GO TO  ENGINE IMMOBILIZER SYSTEM 

  5. CHECK STEERING LOCK SYSTEM 
    1. When the engine switch is on (ACC), check that the steering lock can be released.

      OK: 

      Steering lock can be released. 

    NG: GO TO  ELECTRIC STEERING LOCK 

    OK: Go To Next Step 

  6. CHECK WIRE HARNESS (POWER SOURCE CONTROL ECU - PNP SWITCH OR CLUTCH START SWITCH) 
    Fig 1: Identifying J55 Power Source Control ECU Connectors
    G04044973Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the J55 ECU connector.
    2. Disconnect the E45 or A24 switch connector.
    3. Measure the resistance of the wire harness side connectors.

    Standard resistance 

    POWER SOURCE CONTROL ECU - PNP SWITCH OR CLUTCH START SWITCH

    Tester Connection (Symbols) Specified Condition
    J55-17 (STR1) - E45-4 (A/T) Below 1 ohms
    J55-17 (STR1) - A24-1 (M/T) Below 1 ohms
    J55-17 (STR1) or E45-4 - Body ground (A/T) 10 k ohms or higher
    J55-17 (STR1) or A24-1- Body ground (M/T) 10 k ohms or higher

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go To Next Step 

  7. CHECK WIRE HARNESS (ENGINE ROOM R/B NO. 2 - POWER SOURCE CONTROL ECU) 
    1. Remove the ST CUT relay from the engine room R/B No. 2.
      Fig 2: Identifying J55 Power Source Control ECU Connectors
      G04044974Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Disconnect the J55 ECU connector.
    3. Measure the resistance of the wire harness side connectors.

    Standard resistance 

    ENGINE ROOM R/B NO. 2 - POWER SOURCE CONTROL ECU

    Tester Connection (Symbols) Specified Condition
    Engine room R/B No. 2 ST CUT relay terminal 3 - J55-15 (STR2) Below 1 ohms
    Engine room R/B No. 2 ST CUT relay terminal 3 or J55-15 (STR2) - Body ground 10 k ohms or higher
    Engine room R/B No. 2 ST CUT relay terminal 2- J55-35 (IG2D) Below 1 ohms
    Engine room R/B No. 2 ST CUT relay terminal 2 or J55-35 (IG2D) - Body ground 10 k ohms or higher

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go To Next Step 

  8. CHECK WIRE HARNESS (POWER SOURCE CONTROL ECU - ECM) 
    1. Disconnect the J55 ECU connector.
    2. Disconnect the A5 ECM connector.
    3. Measure the resistance of the wire harness side connectors.

    Standard resistance 

    POWER SOURCE CONTROL ECU - ECM

    Tester Connection (Symbols) Specified Condition
    J55-28 (SKSW) - A5-23 (KSW) Below 1 ohms
    J55-28 (SKSW) or A5-23 (KSW) - Body ground 10 k ohms or higher
    Fig 3: Identifying J55 Power Source Control ECU Connectors
    G04044975Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go To Next Step 

  9. CHECK POWER SOURCE CONTROL ECU 
    1. Reconnect the J55 ECU connector.
      Fig 4: Identifying Power Source Control ECU Connectors
      G04044976Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the voltage of the ECU.

    Standard voltage 

    POWER SOURCE CONTROL ECU

    Tester Connection (Symbols) Condition Specified Condition
    J55-39 (STSW) - Body ground Engine switch on (IG) 10 to 14 V

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: GO TO  SFI SYSTEM 

scientia non olet · About LEMON Manuals