SMART KEY SYSTEM (for Start Function) Engine does not Start

DESCRIPTION

When the key is in the vehicle and the engine switch is pressed, the certification ECU (smart key ECU assembly) receives a signal and changes the power source mode. In addition, when the shift lever is in P or N and the brake pedal is depressed, the engine can be started by pressing the engine switch.

Tech Tips

  • When the certification ECU (smart key ECU assembly) is replaced with a new one and the cable is connected to the negative (-) battery terminal, the power source mode changes to on (IG).

  • When the battery cable is disconnected and reconnected, the power source returns to the mode it was in before the battery cable was disconnected.

WIRING DIAGRAM

Refer to "System Diagram" Click here

INSPECTION PROCEDURE

Note

  • When using the Techstream with the engine switch off, perform either of the following: 1) Turn a courtesy light switch on and off at intervals of 1.5 seconds or less until communication between the Techstream and vehicle begins, or 2) connect the Techstream to the vehicle, select the vehicle type under manual mode, and then enter the following menus: Body Electrical / Smart Key / Trouble Codes.

  • The smart key system (for Start Function) uses a multiplex communication system (LIN communication system) and the CAN communication system. Inspect the communication function by following How to Proceed with Troubleshooting Click here. Troubleshoot the smart key system (for Start Function) after confirming that the communication systems are functioning properly.

  • If the smart key system is disabled through the customize function, enable the system before performing troubleshooting Click here.

  • Before replacing the certification ECU (smart key ECU assembly) or steering lock ECU (steering lock actuator assembly), refer to the smart key system (for Start Function) precaution Click here.

  • Inspect the fuses of circuits related to this system before performing the following inspection procedure.

  • If the steering lock ECU (steering lock actuator assembly) is replaced, be sure to confirm that the steering is unlocked by turning the steering wheel to the left and right before starting the engine. If the steering is locked for any reason, open and close a door with the engine switch off, and then unlock the steering by pressing the engine switch. This prevents the engine from starting while the steering is locked.

  • After completing repairs, confirm that the problem does not occur.

Tech Tips

Related Data List and Active Test Items
Problem Symptom Data List Item Active Test Item
Engine does not start

    Power Source Control

  • Stop Light Switch1

  • Steering Unlock Switch

  • Power Supply Condition

  • IG1 Relay Monitor(Inside)

  • IG2 Relay Monitor(Inside)

  • IG1 Relay Monitor(Outside)

  • IG2 Relay Monitor(Outside)

  • Latch Circuit

  • Shift P Signal

  • Neutral SW/ Clutch SW

  • Starter Request Signal

    Smart Key

  • L Code Check

  • Engine Start Request

  • Immobiliser

    Starting Control

  • Ignition

  • Starter SW

  • Shift Position P or N

 -

Tech Tips

If the brake pedal is repeatedly depressed while the engine is stopped, the brake booster pressure is released and the force required to depress the brake pedal to illuminate the stop lights increases.

PROCEDURE

  1. CHECK BATTERY

    1. Measure the battery voltage.

      Standard voltage
      11 to 14 V

      Tech Tips

      • It may be possible to tell whether the vehicle battery is discharged by operating the horn.

      • If the battery voltage is less than 11 V, charge or replace it.

    OK

  2. CHECK FOR DTC

    1. Using the Techstream, confirm the output of DTCs for all systems.

      OK
      No DTCs are output.

      Note

      Make sure that no DTCs are output. If any DTCs are output, proceed to the Diagnostic Trouble Code Chart.

    NG

    GO TO DTC CHART

    OK

  3. CHECK WAVE ENVIRONMENT

    1. If the problem occurs in certain locations or times of day, the possibility of wave interference is high.

      Tech Tips

      Whether or not the problem is due to wave interference can be checked by holding the electrical key transmitter sub-assembly near the door control receiver (RF band).

    NEXT

  4. CHECK ENGINE SWITCH CONDITION

    1. Get into the vehicle while carrying an electrical key transmitter sub-assembly.

    2. Move the shift lever to P.

    3. With the brake pedal released, check that pressing the engine switch causes the power source mode to change.

      Result
      Result Proceed to
      Off → on (ACC) → on (IG) → off A
      Power source mode does not change to on (ACC) and on (IG) B
      Power source mode changes to on (IG) but not to on (ACC) C
      Power source mode changes to on (ACC) but not to on (IG) D
    B

    GO TO POWER SOURCE MODE DOES NOT CHANGE TO ON (IG AND ACC) Click here

    C

    GO TO POWER SOURCE MODE DOES NOT CHANGE TO ON (IG) Click here

    D

    GO TO POWER SOURCE MODE DOES NOT CHANGE TO ON (ACC) Click here

    A

  5. CHECK CRANKING FUNCTION

    1. Get into the vehicle while carrying an electrical key transmitter sub-assembly.

    2. Move the shift lever to P.

    3. Depress the brake pedal.

    4. w/o Multi-information Display:

      Confirm that the smart warning light is illuminated in green, and then press the engine switch and check that the engine cranks.

    5. w/ Multi-information Display:

      Confirm that the smart warning light is displayed, and then press the engine switch and check that the engine cranks.

      OK
      Engine cranks.
      Result
      Result Proceed to
      NG A
      OK (for 2AR-FE) B
      OK (for 2GR-FE) C
    B

    GO TO SFI SYSTEM (PROBLEM SYMPTOMS TABLE) Click here

    C

    GO TO SFI SYSTEM (PROBLEM SYMPTOMS TABLE) Click here

    A

  6. CHECK SECURITY INDICATOR LIGHT (ENGINE IMMOBILISER SYSTEM UNSET)

    1. Get into the vehicle while carrying an electrical key transmitter sub-assembly.

    2. Move the shift lever to P.

    3. Press the engine switch with the brake pedal released and check that the security indicator light changes from blinking to off at the same time that the power source mode changes to on (ACC).

      OK
      Security indicator light changes from blinking to off at the same time that the power source mode changes to on (ACC).

      Tech Tips

      It is determined that the engine immobiliser function is operating correctly if the security indicator light changes from blinking to off at the same time that the power source mode changes to on (ACC).

    NG

    CHECK STEERING LOCK Click here

    OK

  7. CHECK COMBINATION METER ASSEMBLY

    1. Get into the vehicle while carrying the key, move the shift lever to P, press the engine switch while depressing the brake pedal and check that the combination meter indicator changes.

      OK
      The smart warning light illuminates in green (w/o Multi-information Display). The smart warning light is displayed (w/ Multi-information Display).

      Tech Tips

      If the smart warning light illuminates in green (w/o Multi-information Display) or smart warning light is displayed (w/ Multi-information Display) when the procedure above is performed, the P, N and brake signals can be considered to be normal.

    NG

    READ VALUE USING TECHSTREAM (NEUTRAL SW/ CLUTCH SW, SHIFT POSITION P OR N) Click here

    OK

  8. READ VALUE USING TECHSTREAM (STARTER SW)

    1. Connect the Techstream to the DLC3.

    2. Turn the engine switch on (IG).

    3. Turn the Techstream on.

    4. Enter the following menus: Body Electrical / Starting Control / Data List.

    5. Get into the vehicle while carrying an electrical key transmitter sub-assembly and press the engine switch with the shift lever in P and brake pedal depressed to check if the Data List display changes.

      Starting Control
      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      Starter SW Starter operation request/ON or OFF

      ON: Starter operation requested

      OFF: Starter operation not requested

      		 When malfunctioning, the engine will not crank.
      OK
      The Data List item changes.
    NG

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) Click here

    OK

  9. INSPECT ST RELAY

    1. Remove the ST relay from the engine room relay block and junction block assembly.

      A011SW2E96

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      1 - 2 20°C (68°F) 93.8 to 136.4 Ω
      3 - 5 Battery voltage not applied to terminals 1 and 2 10 kΩ or higher
      Battery voltage applied to terminals 1 and 2 Below 1 Ω

    3. Reinstall the ST relay to the engine room relay block and junction block assembly.

    NG

    REPLACE ST RELAY

    OK

  10. CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) - BODY GROUND)

    1. Disconnect the A43 connector from the certification ECU (smart key ECU assembly).

      A011VB5E09

    2. Move the shift lever to P or N.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A43-5 (STAR) - Body ground 20°C (68°F) 93.75 to 136.36 Ω
      A43-7 (STA) - Body ground
      Text in Illustration
      *a

      Rear view of wire harness connector

      (to Certification ECU (Smart Key ECU Assembly))
    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  11. INSPECT STARTER ASSEMBLY

    1. Inspect the starter assembly (for 2AR-FE) Click here.

    2. Inspect the starter assembly (for 2GR-FE) Click here.

      Result
      Result Proceed to
      OK A
      NG (for 2AR-FE) B
      NG (for 2GR-FE) C
    B

    REPLACE STARTER ASSEMBLY Click here

    C

    REPLACE STARTER ASSEMBLY Click here

    A

  12. CHECK HARNESS AND CONNECTOR (BATTERY - STARTER AND ENGINE ROOM RELAY BLOCK AND JUNCTION BLOCK ASSEMBLY)

    1. Remove the starter assembly from the vehicle to perform an inspection.

    2. Remove the ST relay from the engine room relay block and junction block assembly.

    3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage
      Tester Connection Condition Specified Condition
      F2-1 (B) - Body ground Always 11 to 14 V
      5 - Body ground Always 11 to 14 V

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      3 - E9-1 (ST) Always Below 1 Ω
      3 or E9-1 (ST) - Body ground Always 10 kΩ or higher
    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) Click here

  13. CHECK STEERING LOCK

    1. Check that the steering unlocks when the engine switch is turned on (ACC).

      OK
      The steering unlocks.
    NG

    READ VALUE USING TECHSTREAM (STEERING UNLOCK SWITCH) Click here

    OK

  14. READ VALUE USING TECHSTREAM (IMMOBILISER)

    1. Connect the Techstream to the DLC3.

    2. Turn the engine switch on (IG).

    3. Turn the Techstream on.

    4. Enter the following menus: Body Electrical / Smart Key / Data List.

    5. According to the display on the Techstream, read the Data List.

      Smart Key
      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      Immobiliser Engine immobiliser system determined by certification ECU (smart key ECU assembly)/ Set or Unset

      Set: Engine immobiliser system set (engine start prohibited) (engine switch off)

      Unset: Engine immobiliser system unset (engine start permitted) (engine switch on (ACC) or on (IG))

      • The engine cannot be started when Set is displayed.

      Tech Tips

      • The security indicator light blinks when Set is displayed.

      • The security indicator light is linked with set/unset of the immobiliser and not linked with steering lock/unlock.
      OK
      The Data List item changes to "unset" when the engine switch is turned on (ACC) or on (IG).
    NG

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) Click here

    OK

  15. READ VALUE USING TECHSTREAM (STARTER REQUEST SIGNAL)

    1. Connect the Techstream to the DLC3.

    2. Turn the engine switch on (IG).

    3. Turn the Techstream on.

    4. Enter the following menus: Body Electrical / Power Source Control / Data List.

    5. According to the display on the Techstream, read the Data List.

      Power Source Control
      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      Starter Request Signal Engine start request signal status/ON or OFF

      ON: With the shift lever in P and brake pedal depressed, the engine switch is pressed and held

      OFF: After approx. 1 sec. has elapsed, the engine switch is released

      • When the engine cannot be started due to a start request signal malfunction, OFF is displayed.

      • When the engine switch is pressed, the duration of time that ON is displayed will be extremely short. As such, the engine switch needs to be pressed and held for a certain amount of time.

      Note

      • w/o Multi-information Display:

        Check that the smart warning light on the combination meter assembly illuminates in green, and then press the engine switch.

      • w/ Multi-information Display:

        Check that the smart warning is displayed on the multi-information display on the combination meter assembly, and then press the engine switch.

      OK
      The display changes in response to the operation of the engine switch.
    NG

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) Click here

    OK

    END Click here

  16. READ VALUE USING TECHSTREAM (NEUTRAL SW/ CLUTCH SW, SHIFT POSITION P OR N)

    1. Connect the Techstream to the DLC3.

    2. Turn the engine switch on (IG).

    3. Turn the Techstream on.

    4. Enter the following menus: Body Electrical / Power Source Control or Starting Control / Data List.

    5. According to the display on the Techstream, read the Data List.

      Power Source Control
      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      Neutral SW/ Clutch SW Shift position (P and N)/ON or OFF

      ON: Shift lever in P or N

      OFF: Shift lever in any position other than P or N

      • Use this item to determine whether the park/neutral position switch is malfunctioning.

      • When the engine cannot be started due to a park/neutral position switch malfunction, OFF is displayed.
      Starting Control
      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      Shift Position P or N Park/neutral position switch status/ON or OFF

      ON: Shift lever in P or N

      OFF: Shift lever in any position other than P or N

      		 When malfunctioning, the engine will not crank.
      OK
      The item in the Data List changes according to the shift position.
    NG

    CHECK PARK/NEUTRAL POSITION SWITCH ASSEMBLY Click here

    OK

  17. READ VALUE USING TECHSTREAM (STOP LIGHT SWITCH1)

    1. Connect the Techstream to the DLC3.

    2. Turn the engine switch on (IG).

    3. Turn the Techstream on.

    4. Enter the following menus: Body Electrical / Power Source Control / Data List.

    5. According to the display on the Techstream, read the Data List.

      Power Source Control
      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      Stop Light Switch1 State of brake pedal/ON or OFF

      ON: Brake pedal depressed

      OFF: Brake pedal released

      • Use this item to determine whether the stop light switch is malfunctioning.

      • The engine cannot be started when this item is OFF.

      • When this item is malfunctioning, the engine can be started by pressing and holding the engine switch for a certain period of time.
      OK
      The item in the Data List changes when the brake pedal is depressed and released.
    NG

    INSPECT STOP LIGHT SWITCH ASSEMBLY Click here

    OK

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) Click here

  18. CHECK PARK/NEUTRAL POSITION SWITCH ASSEMBLY

    1. Disconnect the E4 park/neutral position switch assembly connector.

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

      A011V9OE18
      Standard Resistance
      Tester Connection Condition Specified Condition
      4 (B) - 9 (L) Shift lever in P or N Below 1 Ω
      Shift lever in any position other than P or N 10 kΩ or higher
      Text in Illustration
      *a

      Component without harness connected

      (Park/Neutral Position Switch Assembly)
      Result
      Result Proceed to
      OK A
      NG (for U660E) B
      NG (for U760E) C
    B

    REPLACE PARK/NEUTRAL POSITION SWITCH ASSEMBLY Click here

    C

    REPLACE PARK/NEUTRAL POSITION SWITCH ASSEMBLY Click here

    A

  19. CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) - PARK/NEUTRAL POSITION SWITCH)

    1. Disconnect the A43 connector from the certification ECU (smart key ECU assembly).

    2. Disconnect the E4 connector from the park/neutral position switch.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A43-5 (STAR) - E4-4 (B) Always Below 1 Ω
      A43-5 (STAR) or E4-4 (B) - Body ground Always 10 kΩ or higher

    4. Reconnect the park/neutral position switch assembly connector.

    5. Measure the voltage according to the value(s) in the table below.

      A011VB5E10
      Standard Voltage
      Tester Connection Condition Specified Condition
      A43-5 (STAR) - Body ground Engine switch pressed and held with brake pedal depressed (starter on) → Engine switch released after approximately 1 second elapses (starter off) 6 V or higher* → 1.5 V or less
      Text in Illustration
      *a

      Rear view of wire harness connector

      (to Certification ECU (Smart Key ECU Assembly))

      Tech Tips

      *: When the engine is cranking, the battery voltage may momentarily drop to approximately 6 V.

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) Click here

  20. INSPECT STOP LIGHT SWITCH ASSEMBLY

    1. Disconnect the A33 connector from the stop light switch assembly.

    2. Inspect the stop light switch assembly Click here.

    NG

    REPLACE STOP LIGHT SWITCH ASSEMBLY Click here

    OK

  21. CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) - STOP LIGHT SWITCH ASSEMBLY)

    1. Disconnect the A33 connector from the stop light switch assembly.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A43-18 (STP1) - A33-1 Always Below 1 Ω
      A43-18 (STP1) or A33-1 - Body ground Always 10 kΩ or higher

    3. Reconnect the A43 stop light switch assembly connector.

      A011UO7E02

    4. Measure the voltage according to the value(s) in the table below.

      Standard Voltage
      Tester Connection Condition Specified Condition
      A43-18 (STP1) - Body ground Brake pedal released 1 V or less
      Brake pedal depressed 9 V or higher
      Text in Illustration
      *a

      Rear view of wire harness connector

      (Certification ECU (Smart Key ECU Assembly))
    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) Click here

  22. READ VALUE USING TECHSTREAM (STEERING UNLOCK SWITCH)

    1. Connect the Techstream to the DLC3.

    2. Turn the engine switch on (IG).

    3. Turn the Techstream on.

    4. Enter the following menus: Body Electrical / Power Source Control / Data List.

    5. According to the display on the Techstream, read the Data List.

      Power Source Control
      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      Steering Unlock Switch State of steering unlock sensor signal output from steering lock actuator assembly/ON or OFF

      ON: Steering unlocked

      OFF: Steering locked

      • When the shift lever is in P and the engine switch is off, if any door is opened or closed, the steering is locked.

      • When the key is inside the vehicle and the engine switch is turned on (ACC) or on (IG), the steering unlocks.

      • The engine cannot be started when the steering unlock signal is off.
      OK
      The item in the Data List indicates "ON" (the steering is unlocked).
    NG

    READ VALUE USING TECHSTREAM (L CODE CHECK) Click here

    OK

    GO TO STEERING LOCK SYSTEM (UNABLE TO UNLOCK STEERING WHEEL) Click here

  23. READ VALUE USING TECHSTREAM (L CODE CHECK)

    1. Connect the Techstream to the DLC3.

    2. Turn the engine switch on (IG).

    3. Turn the Techstream on.

    4. Enter the following menus: Body Electrical / Smart Key / Data List.

    5. According to the display on the Techstream, read the Data List.

      Smart Key
      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      L Code Check Verification result between certification ECU (smart key ECU assembly) and steering lock ECU (steering lock actuator assembly)/OK or NG

      OK: Verification result normal

      NG: Verification result abnormal

      • When NG is displayed:

      • L code has not been registered for the certification ECU (smart key ECU assembly) or steering lock ECU (steering lock actuator assembly).

      • Steering cannot be locked.

      • Steering cannot be unlocked (the engine cannot be started).
      OK
      The Data List item changes to "OK" when the key is inside the vehicle.

      Tech Tips

      Reasons for verification failure:

      • The steering lock ECU is malfunctioning.

      • There is a problem with the communication between ECUs.

      • An ECU is replaced, but is not registered.

      • An ECU is replaced with an ECU which has a code already stored in it.

    NG

    REPLACE STEERING LOCK ECU (STEERING LOCK ACTUATOR ASSEMBLY) Click here

    OK

  24. REPLACE STEERING LOCK ECU (STEERING LOCK ACTUATOR ASSEMBLY)

    1. Replace the steering lock ECU (steering lock actuator assembly) with a new one Click here.

    2. Perform the registration procedures Click here.

    3. Turn the engine switch on (IG).

    4. Operate the steering wheel and check the steering condition.

    NEXT

    END (STEERING LOCK ECU (STEERING LOCK ACTUATOR ASSEMBLY) WAS DEFECTIVE)

  25. REPLACE STEERING LOCK ECU (STEERING LOCK ACTUATOR ASSEMBLY)

    1. Replace the steering lock ECU (steering lock actuator assembly) with a new one Click here.

    2. Perform the registration procedures Click here.

    3. Use the Data List to check if L code certification is functioning properly again.

      Smart Key
      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      L Code Check Verification result between certification ECU (smart key ECU assembly) and steering lock ECU (steering lock actuator assembly)/OK or NG

      OK: Verification result normal

      NG: Verification result abnormal

      • When NG is displayed:

      • L code has not been registered for the certification ECU (smart key ECU assembly) or steering lock ECU (steering lock actuator assembly).

      • Steering cannot be locked.

      • Steering cannot be unlocked (the engine cannot be started).
      OK
      OK (L code certification result normal) appears on the screen.
    NG

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) Click here

    OK

    END (STEERING LOCK ECU (STEERING LOCK ACTUATOR ASSEMBLY) WAS DEFECTIVE)