Entry And Start System Engine Does Not Start

Engine. Lexus Is250, Is220D. Gse20 Ale20
4Gr-Fse Starting. Lexus Is250, Is220D. Gse20 Ale20

DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

CHECK IF ENGINE START (INITIALIZE STEERING LOCK)

CHECK FOR DTC

CHECK SWITCH CONDITION

CHECK CRANKING FUNCTION

READ VALUE OF INTELLIGENT TESTER (STA SIGNAL)

READ VALUE OF INTELLIGENT TESTER (STOP LIGHT SWITCH)

READ VALUE OF INTELLIGENT TESTER (STEERING LOCK)

CHECK STEERING LOCK

INSPECT ECM (STAR AND STSW VOLTAGE)

INSPECT RELAY (ST CUT)

INSPECT PARK/NEUTRAL POSITION SWITCH (A/T) OR CLUTCH START SWITCH (M/T)

INSPECT RELAY (STARTER)

CHECK HARNESS AND CONNECTOR (PNP SWITCH (A/T) OR CLUTCH START SWITCH (M/T) - ST RELAY)

INSPECT ENGINE ROOM RELAY BLOCK (STARTER RELAY VOLTAGE)

INSPECT STARTER ASSEMBLY

CHECK HARNESS AND CONNECTOR (POWER SOURCE CONTROL ECU - ECM)

CHECK AND REPLACE POWER SOURCE CONTROL ECU

READ VALUE OF INTELLIGENT TESTER (L CODE)

READ VALUE OF INTELLIGENT TESTER (ENGINE START REQUEST)

READ VALUE OF INTELLIGENT TESTER (S CODE)

INSPECT ID CODE BOX

CHECK WIRE HARNESS (POWER SOURCE CONTROL ECU - STEERING LOCK ECU)

INSPECT POWER SOURCE CONTROL ECU

INSPECT STEERING LOCK ECU

ENTRY AND START SYSTEM - Engine does not Start


DESCRIPTION


ENGINE START SYSTEM OPERATION

  1. A/T Models: If the engine switch is pressed with the shift lever in P or N and the brake pedal depressed, the power source control ECU determines that it is an engine start request.

  2. M/T Models: If the engine switch is pressed with the clutch pedal depressed, the power source control ECU determines that it is an engine start request.

  3. The certification ECU and other ECUs perform key verification via the LIN communication line.

  4. The power source control ECU activates the ACC relay.

  5. The power source control ECU activates the IG1 and IG2 relays.

  6. The certification ECU outputs a steering UNLOCK signal. The signal is sent to the power source control ECU via the steering lock ECU.

  7. The power source control ECU sends an engine start request signal to the ECM.

  8. The ECM sends an ACC cut request signal to the power source control ECU.

  9. The ECM and power source control ECU activate the ST relay.

  10. The power source control ECU deactivates the ACC relay until the ECU detects an engine start.

  11. When engine revolution speed reaches 200 rpm, the power source control ECU determines that the engine has been started.
    The ECU reactivates the ACC relay and turns off the engine switch indicator light.

    Symbols of power source control ECU
    		Signals
    STP
    		Stop light switch ON signal
    SSW1/SSW2
    		Engine switch ON signal
    ACCD
    		ACC relay operation signal
    IG2D
    		IG2 relay operation signal
    STR2
    		ST relay operation signal
    STR1
    		Park/neutral position switch signal (A/T), Clutch start switch (M/T)
    TACH
    		Engine start detection signal
    STSW
    		Starter activation request signal
    CTSW
    		ACC cut request signal

Lexus Is250, Is220D. Gse20 Ale20.4Gr-Fse Starting.Starting System.Entry And Start System Engine Does Not Start


WIRING DIAGRAM

See CRANKING HOLDING FUNCTION CIRCUIT (Click here).

INSPECTION PROCEDURE

1.CHECK IF ENGINE START (INITIALIZE STEERING LOCK)

  1. Shift lever is in the P position.

  1. Open and close the driver's door with the engine switch off. Check if the engine can be started.

    OK:
    Engine can be started.
    HINT:
    After the battery is discharged and then recharged, the engine may not start unless the steering lock is initialized using the above procedure.


OK
END
NG


2.CHECK FOR DTC

  1. Delete the DTCs (Click here).

  1. Check for DTCs again.

    OK:
    No DTC is output.


NG
GO TO DTC CHART
OK


3.CHECK SWITCH CONDITION

  1. Check the engine start function.

    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 that pressing the engine switch causes the power source mode to change as follows.

      OK:
      off, on (IG), on (ACC), off.
      HINT:
      1. If power mode does not change to ON (IG and ACC) (Click here).
      2. If power mode does not change to ON (IG) (Click here).
      3. If power mode does not change to ON (ACC) (Click here).


NG
PROCEED TO APPROPRIATE PROBLEM SYMPTOMS SHOWN IN PROBLEM SYMPTOMS TABLE
OK


4.CHECK CRANKING 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 crank the engine.

    2. M/T Models: When there is fuel in the tank and the key is inside the vehicle, check that depressing the clutch pedal and the brake pedal and pressing the engine switch crank the engine.

      OK:
      Engine cranks.


OK
Go to step 18
NG


5.READ VALUE OF INTELLIGENT TESTER (STA SIGNAL)

  1. Connect the intelligent tester to the DLC3.

  1. Turn the engine switch on (IG).

  1. Check the result when the engine switch is turned on (IG) and the engine is started.

    Standard:
    Engine Switch Position
    		ON (IG)
    		ENGINE START
    St Relay Mon
    		OFF
    		ON
    OK:
    ON (ENGINE START) and OFF (ENGINE SWITCH ON (IG)) appear on the screen.


OK
Go to step 12
NG


6.READ VALUE OF INTELLIGENT TESTER (STOP LIGHT SWITCH)

  1. Connect the intelligent tester to the DLC3.

  1. Turn the engine switch on (IG).

  1. Check the DATA LIST for proper functioning of the stop light switch.

    Power Source Control:
    Item
    		Measurement Item/Display (Range)
    		Normal Condition
    		Diagnostic Note
    Stop Lamp SW1
    		Stop light Switch 1/ ON or OFF
    		ON: Brake pedal depressed
    OFF: Brake pedal released
    		-
    OK:
    ON (brake pedal (A/T) or clutch pedal (M/T) depressed) and OFF (brake pedal (A/T) or clutch pedal (M/T) released) appear on the screen.
    HINT:
    If the result of the inspection for a tester display is not as specified, perform troubleshooting for DTC B2284 first (Click here).


NG
GO TO DTC CHART
OK


7.READ VALUE OF INTELLIGENT TESTER (STEERING LOCK)

  1. Connect the intelligent tester to the DLC3.

  1. Turn the engine switch on (IG).

    Power Source Control:
    Item
    		Measurement Item/Display (Range)
    		Normal Condition
    		Diagnostic Note
    Str Unlock SW
    		Steering lock condition/ ON or OFF
    		ON: Steering is unlocked
    OFF: Steering is locked
    		-
    OK:
    ON (steering is unlocked) and OFF (steering is locked) appear on the screen.


NG
Go to step 22
OK


8.CHECK STEERING LOCK

  1. Check if the steering lock is released when turning the engine switch on (ACC).

    OK:
    The steering lock is released.


NG
GO TO STEERING LOCK SYSTEM
OK


9.INSPECT ECM (STAR AND STSW VOLTAGE)


    Lexus Is250, Is220D. Gse20 Ale20.4Gr-Fse Starting.Starting System.Entry And Start System Engine Does Not Start

  1. Measure the voltage of the A5 and E4 ECM connectors while cranking the engine.

    Standard voltage:
    Tester Connection
    		Specified Condition
    STAR (E4-4) - E1 (E4-7)
    		9 to 14 V
    STSW (A5-19) - E1 (E4-7)
    		9 to 14 V
    Result:
    Terminal STAR
    		Terminal STSW
    		Proceed to
    9 to 14 V
    		9 to 14 V
    		A
    0 V
    		9 to 14 V
    		B
    0 V
    		0 V
    		C


B
REPLACE ECM

C
Go to step 16
A


10.INSPECT RELAY (ST CUT)


    Lexus Is250, Is220D. Gse20 Ale20.4Gr-Fse Starting.Starting System.Entry And Start System Engine Does Not Start

  1. Remove the ST CUT relay from the engine room J/B and R/B No. 2.

  1. Measure the resistance of the ST CUT relay.

    Standard resistance:
    Tester Connection
    		Specified Condition
    3 - 5
    		10 kΩ or higher
    3 - 5
    		Below 1 Ω
    (when battery voltage applied to terminals 1 and 2)


NG
REPLACE RELAY
OK


11.INSPECT PARK/NEUTRAL POSITION SWITCH (A/T) OR CLUTCH START SWITCH (M/T)


    Lexus Is250, Is220D. Gse20 Ale20.4Gr-Fse Starting.Starting System.Entry And Start System Engine Does Not Start

  1. Disconnect the park/neutral position (PNP) switch (A/T) or clutch switch (M/T) connector.

  1. Measure the resistance between each terminal shown below when the shift lever is moved to each range.

    Standard resistance (A/T):
    Shift Position
    		Tester Connection
    		Specified Condition
    P
    		4 - 5
    		Below 1 Ω
    N
    		4 - 5
    		Below 1 Ω
    Except N or P
    		4 - 5
    		10 kΩ or higher
    Standard resistance (M/T):
    Clutch Pedal Operation
    		Tester Connection
    		Specified Condition
    Depressed
    		1 - 2
    		Below 1 Ω
    Released
    		1 - 2
    		10 kΩ or higher


NG
REPLACE PNP SWITCH (A/T) OR CLUTCH START SWITCH (M/T)
OK

CHECK AND REPLACE HARNESS AND CONNECTOR (PARK/NEUTRAL POSITION SWITCH - ECM, ECM - ST CUT RELAY, ST)

12.INSPECT RELAY (STARTER)


    Lexus Is250, Is220D. Gse20 Ale20.4Gr-Fse Starting.Starting System.Entry And Start System Engine Does Not Start

  1. Remove the starter relay from the engine room J/B and R/B No. 1.

  1. Measure the resistance of the starter relay.

    Standard resistance:
    Tester Connection
    		Specified Condition
    3 - 5
    		10 kΩ or higher
    3 - 5
    		Below 1 Ω
    (when battery voltage applied to terminals 1 and 2)


NG
REPLACE RELAY
OK


13.CHECK HARNESS AND CONNECTOR (PNP SWITCH (A/T) OR CLUTCH START SWITCH (M/T) - ST RELAY)


    Lexus Is250, Is220D. Gse20 Ale20.4Gr-Fse Starting.Starting System.Entry And Start System Engine Does Not Start

  1. Check the harness and the connectors between the park/neutral position switch and the starter relay.

    1. Disconnect the E45*1 or A24*2 switch connector.
      *1: A/T
      *2: M/T

    2. Remove the starter relay from the engine room J/B and R/B No. 1.

    3. Measure the resistance of the wire harness side connectors.

      Standard resistance (A/T) (Check for open):
      Tester Connection
      		Specified Condition
      Park/Neutral position switch (E45-5) - Starter relay (1)
      		Below 1 Ω
      Standard resistance (M/T) (Check for open):
      Tester Connection
      		Specified Condition
      Clutch start switch (A24-2) - Starter relay (1)
      		Below 1 Ω
      Standard resistance (A/T) (Check for short):
      Tester Connection
      		Specified Condition
      Park/Neutral position switch (E45-5) or Starter relay (1) - Body ground
      		10 kΩ or higher
      Standard resistance (M/T) (Check for short):
      Tester Connection
      		Specified Condition
      Clutch start switch (A24-2) or Starter relay (1) - Body ground
      		10 kΩ or higher

  1. Check the harness and the connector between the starter relay and the body ground.

    1. Remove the starter relay from the engine room J/B and R/B No. 1.

    2. Measure the resistance of the starter relay and the body ground.

      Standard resistance (Check for open):
      Tester Connection
      		Specified Condition
      Starter relay (2) - Body ground
      		Below 1 Ω


NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK


14.INSPECT ENGINE ROOM RELAY BLOCK (STARTER RELAY VOLTAGE)


    Lexus Is250, Is220D. Gse20 Ale20.4Gr-Fse Starting.Starting System.Entry And Start System Engine Does Not Start

  1. Remove the starter relay from the engine room J/B and R/B No. 1.

  1. Measure the voltage of the engine room J/B and R/B No. 1 and the body ground.

    Standard voltage:
    Tester Connection
    		Specified Condition
    Starter relay (5) - Body ground
    		9 to 14 V


NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK


15.INSPECT STARTER ASSEMBLY
HINT:
Click here.


NG
REPAIR OR REPLACE STARTER ASSEMBLY
OK

REPAIR OR REPLACE HARNESS OR CONNECTOR (STARTER RELAY - STARTER, STARTER - BATTERY)

16.CHECK HARNESS AND CONNECTOR (POWER SOURCE CONTROL ECU - ECM)


    Lexus Is250, Is220D. Gse20 Ale20.4Gr-Fse Starting.Starting System.Entry And Start System Engine Does Not Start

  1. Check the harness and the connectors between the power source control ECU and ECM.

    1. Disconnect the power source control ECU connector.

    2. Disconnect the A5 ECM connector.

    3. Measure the resistance of the wire harness side connectors.

      Standard resistance (Check for open):
      Tester Connection
      		Specified Condition
      J55-39 (STSW) - A5-19 (STSW)
      		Below 1 Ω
      Standard resistance (Check for short):
      Tester Connection
      		Specified Condition
      J55-39 (STSW) or A5-19 (STSW) - Body ground
      		10 kΩ or higher


NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK


17.CHECK AND REPLACE POWER SOURCE CONTROL ECU

  1. Replace the power source control ECU.

  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 crank the engine.

    2. M/T Models: When there is fuel in the tank and the key is inside the vehicle, check that depressing the clutch pedal and the brake pedal and pressing the engine switch crank the engine.

      OK:
      Engine cranks.
      HINT:
      After the power source control ECU is replaced, the engine may not start unless each system is initialized using the above procedure.


NG
REPLACE ECM
OK

END

18.READ VALUE OF INTELLIGENT TESTER (L CODE)

  1. Reconnect the connectors.

  1. Connect the intelligent tester to the DLC3.

  1. Turn the engine switch on (IG).

    Entry & Start:
    Item
    		Measurement Item/Display (Range)
    		Normal Condition
    		Diagnostic Note
    L Code Chk
    		L code check/ ON or NG
    		OK: Normal
    NG: Malfunction
    		Electrical key in the cabin
    OK:
    OK is displayed on the screen.
    HINT:
    If the result of the inspection for a tester display is not as specified, there may be malfunction of the steering lock ECU or the ID code box.


NG
GO TO ENGINE IMMOBILISER SYSTEM
OK


19.READ VALUE OF INTELLIGENT TESTER (ENGINE START REQUEST)

  1. Connect the intelligent tester to the DLC3.

  1. Turn the engine switch on (IG).

    Entry & Start:
    Item
    		Measurement Item/Display (Range)
    		Normal Condition
    		Diagnostic Note
    Start Rqst
    		Start request signal response/ OK or NG
    		OK: Received
    NG: Non-received
    		-
    OK:
    OK (received) and NG (non-received) appear on the screen.


NG
REPLACE CERTIFICATION ECU
OK


20.READ VALUE OF INTELLIGENT TESTER (S CODE)

  1. Connect the intelligent tester to the DLC3.

  1. Turn the engine switch on (IG).

    Entry & Start:
    Item
    		Measurement Item/Display (Range)
    		Normal Condition
    		Diagnostic Note
    S Code Chk
    		S code check/ OK or NG
    		OK: Normal
    NG: Malfunction
    		-
    OK:
    OK is displayed on the screen.
    HINT:
    If the result of the inspection for a tester display is not as specified, there may be malfunction of the certification ECU or the ID code box.


NG
GO TO ENGINE IMMOBILISER SYSTEM
OK


21.INSPECT ID CODE BOX


    Lexus Is250, Is220D. Gse20 Ale20.4Gr-Fse Starting.Starting System.Entry And Start System Engine Does Not Start

  1. Check the input signal waveform.

    1. Connect the oscilloscope to the terminals J69-6 (EFIO) and A6-6 (IMI).

    2. Turn the engine switch on (IG).

    3. Check the signal waveform according to the condition(s) in the table below.

      Item
      		Condition
      Tool setting
      		10 V/DIV., 100 ms./DIV.
      Vehicle condition
      		Engine switch on (IG)


NG
REPLACE ID CODE BOX
OK

END

22.CHECK WIRE HARNESS (POWER SOURCE CONTROL ECU - STEERING LOCK ECU)


    Lexus Is250, Is220D. Gse20 Ale20.4Gr-Fse Starting.Starting System.Entry And Start System Engine Does Not Start

  1. Disconnect the ECU connector.

  1. Measure the resistance according to the value(s) in the table below.

    Standard resistance:
    Tester Connection (Symbols)
    		Specified Condition
    J55-26 (SLP) - J29-4 (SLP1)
    		Below 1 Ω
    J55-26 (SLP) or J29-4 (SLP1) - Body ground
    		10 kΩ or higher


NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK


23.INSPECT POWER SOURCE CONTROL ECU


    Lexus Is250, Is220D. Gse20 Ale20.4Gr-Fse Starting.Starting System.Entry And Start System Engine Does Not Start

  1. Reconnect the J55 ECU connector.



    Lexus Is250, Is220D. Gse20 Ale20.4Gr-Fse Starting.Starting System.Entry And Start System Engine Does Not Start

  1. Connect the oscilloscope to the power source control ECU terminals specified in the table below and check the waveform.

    Item
    		Contents
    Terminal (Symbols)
    		J55-26 (SLP) - Body ground
    Equipment Setting
    		2 V/DIV., 100 ms./DIV.
    Condition
    		Engine switch on (IG)
    OK:
    The waveform appears as shown in the illustration.


NG
REPLACE POWER SOURCE CONTROL ECU
OK


24.INSPECT STEERING LOCK ECU


    Lexus Is250, Is220D. Gse20 Ale20.4Gr-Fse Starting.Starting System.Entry And Start System Engine Does Not Start

  1. Reconnect the J29 ECU connector.



    Lexus Is250, Is220D. Gse20 Ale20.4Gr-Fse Starting.Starting System.Entry And Start System Engine Does Not Start

  1. Connect the oscilloscope to the power source control ECU terminals specified in the table below and check the waveform.

    Item
    		Contents
    Terminal (Symbols)
    		J55-26 (SLP) - Body ground
    Equipment Setting
    		2 V/DIV., 100 ms./DIV.
    Condition
    		Steering is LOCK / UNLOCK
    OK:
    The waveform appears as shown in the illustration.


NG
REPLACE STEERING LOCK ECU
OK

REPLACE POWER SOURCE CONTROL ECU