PUSH-BUTTON START SYSTEM Room Oscillator does not Recognize Key

DESCRIPTION

If code verification cannot be performed in the vehicle interior, there may be problems with the communication between the vehicle (indoor electrical key antenna assembly [front floor], [rear floor] or [inside luggage]) and key, or the certification ECU (smart key ECU assembly) may be malfunctioning. When the key is brought into the vehicle, verification of the key ID code transmitted from the key and the key ID code stored in the certification ECU (smart key ECU assembly) is performed. If verification cannot be performed or the codes do not match, the power switch cannot be turned on (IG) and the hybrid control system cannot be started.

When a door is unlocked and the key is brought into the vehicle, the certification ECU (smart key ECU assembly) activates the indoor electrical key antenna assembly which transmits electric waves to detect the key. If the key recognizes that it is in the detection area, it responds with the key ID code. This information is received by the indoor electrical key antenna and then sent to the certification ECU (smart key ECU assembly).

WIRING DIAGRAM

A003Z5BE10

INSPECTION PROCEDURE

Note


  • When using the intelligent tester with the power 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 intelligent tester and vehicle begins, or 2) connect the intelligent tester to the vehicle, select the vehicle type under manual mode, and then enter the following menus:

    for Power Source Control: Body / Power Source Control / DTC.

    for Entry&Start: Body / Entry&Start / DTC.

  • The push-button start system uses multiplex communication. First perform the inspections in "How to Proceed with Troubleshooting" to confirm that there are no communication malfunctions before proceeding with troubleshooting Click here

  • After performing repairs, perform the operation that fulfills the DTC output confirmation operation, and then confirm that no DTCs are output again.

  • When replacing the certification ECU (smart key ECU assembly), registration must be performed refer to the Service Bulletin.

  • Indoor electrical key antenna assembly have an antenna coil between each two CLG terminals.

PROCEDURE


  1. CHECK WIRELESS DOOR LOCK CONTROL SYSTEM


    1. Check that the wireless door lock control system Click here.


    NG

    GO TO PROBLEM SYMPTOMS TABLE Click here

    OK

  2. CHECK PUSH-BUTTON START SYSTEM


    1. A003X6TE01
      Text in Illustration
      *1 Power Switch
      *2 Electrical Key Transmitter

      Remove the battery of the electrical key transmitter Click here.

    2. With the brake pedal depressed, touch the LEXUS mark of the key to the power switch.

    3. When operating the power switch, check whether the hybrid control system starts.

      Tech Tips


      • When the key cannot be verified even though it is inside the detection area, the hybrid control system start check can be performed by removing the battery from the key and holding the key against the power switch.

      • If the hybrid control system cannot be started when performing this inspection, the certification ECU (smart key ECU assembly) or ID code box (immobiliser code ECU) may be malfunctioning.

      OK
      Hybrid control system starts.

    NG

    GO TO OTHER FLOW CHART (Power Source Mode does not Change to ON (IG and ACC)) Click here

    OK

  3. CHECK WAVE ENVIRONMENT


    1. Install the battery to the electrical key transmitter Click here.

    2. Bring the electrical key transmitter near the door control receiver and perform a push-button start system check.

      Tech Tips

      As the effect of electric wave interference decreases by moving the key close to the door control receiver, it may be possible to check whether electric wave interference is the cause of the problem.

      Result
      Result Proceed to
      System cannot be operated A
      System can be operated B

      Tech Tips


      • If the problem only occurs in specific places or at specific times, electric wave interference may be the cause of the problem . Also, the vehicle may be have the effects of electric wave interference with the parts installed by the dealer. As a result, when parts have been installed by the dealer, it may be necessary to remove those parts before inspecting the vehicle.

      • There may be electric wave interference if the vehicle is near broadcasting antennas, large video displays, wireless garage door opener systems, wireless security cameras, home security systems, etc. In this case, move the vehicle to a different location and check if there is any improvement.

      • If a tool for checking electric waves, such as a signal strength meter, is available, move around the area while observing both the LF band (used by the vehicle antenna to form the key detection area) and RF band (used by the key for transmission) to check for locations where there is electric wave interference.


    B

    AFFECTED BY WAVE INTERFERENCE

    A

  4. CHECK ELECTRICAL KEY ANTENNAS IN KEY DIAGNOSTIC MODE


    1. Check the following antennas in the key diagnostic mode Click here.


      1. A003ZGKE01
        Text in Illustration
        *a Inspection Point

        Check the No. 1 indoor electrical key antenna assembly (front floor).

        When the electrical key transmitter is at the inspection point, check that the wireless door lock buzzer sounds.

      2. A003WGGE01
        Text in Illustration
        *a Inspection Point

        Check the No. 2 indoor electrical key antenna assembly (rear floor).

        When the electrical key transmitter is at the inspection point, check that the wireless door lock buzzer sounds.

      3. A003VIDE01
        Text in Illustration
        *a Inspection Point

        Check the No. 3 indoor electrical key antenna assembly (inside luggage).

        When the electrical key transmitter is at the inspection point, check that the wireless door lock buzzer sounds.

        Tech Tips


        • If the buzzer sounds, it can be determined that the vehicle interior transmitters are operating normally.

        • It is possible to check which indoor electrical key antenna assembly (front floor, rear floor or inside luggage) is operating by the sounding of the buzzer.

        • If the buzzer does not sound for any indoor electrical key antenna assemblies, the certification ECU (smart key ECU assembly) circuit may have a malfunction.

        OK
        Wireless door lock buzzer sounds.
        Result
        Result Proceed to
        Front operation check fails A
        Rear operation check fails B
        Luggage operation check fails C
        Front, rear and luggage operation checks are normal D

    B

    CHECK HARNESS AND CONNECTOR (NO. 2 INDOOR ELECTRICAL KEY ANTENNA - CERTIFICATION ECU) Click here

    C

    CHECK HARNESS AND CONNECTOR (NO. 3 INDOOR ELECTRICAL KEY ANTENNA - CERTIFICATION ECU) Click here

    D

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)

    A

  5. CHECK HARNESS AND CONNECTOR (NO. 1 INDOOR ELECTRICAL KEY ANTENNA - CERTIFICATION ECU)


    1. Disconnect the H74 No. 1 indoor electrical key antenna assembly (front floor) connector.

    2. Disconnect the H143 certification ECU (smart key ECU assembly) connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      H74-1 (CLG3) - H143-7 (CLG5) Always Below 1 Ω
      H74-3 (CLGB) - H143-8 (CG5B) Always Below 1 Ω
      H74-1 (CLG3) or H143-7 (CLG5) - Body ground Always 10 kΩ or higher
      H74-3 (CLGB) or H143-8 (CG5B) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  6. CHECK CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) (OUTPUT TO NO. 1 INDOOR ELECTRICAL KEY ANTENNA [FRONT FLOOR])


    1. A003XFAE12
      Text in Illustration
      *1 Waveform
      *a

      Front view of wire harness connector

      (to No. 1 indoor Electrical Key Antenna [Front Floor])
      *b Door open
      *c After approximately 30 seconds from when the door is closed

      Disconnect the H74 No. 1 indoor electrical key antenna assembly (front floor) connector.

    2. Reconnect the H143 certification ECU (smart key ECU assembly) connector.

    3. Using an oscilloscope, check the waveform.

      OK
      Tester Connection Switch Condition Tool Setting Specified Condition
      H74-1 (CLG3) - H74-3 (CLGB)

      Procedure:


      1. Power switch off

      2. Door is open

      3. Door is closed

      4. 30 seconds elapse

      		 2 V/DIV., 500 ms/DIV. Pulse generation (See waveform)

    NG

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)

    OK

  7. REPLACE NO. 1 INDOOR ELECTRICAL KEY ANTENNA ASSEMBLY (FRONT FLOOR)


    1. Temporarily replace the No. 1 indoor electrical key antenna assembly (front floor) with a new or normally functioning one Click here.


    NEXT

  8. CHECK ELECTRICAL KEY ANTENNA IN KEY DIAGNOSTIC MODE


    1. Check the following antenna in the key diagnostic mode Click here.


      1. A003ZGKE01
        Text in Illustration
        *a Inspection Point

        Check the No. 1 indoor electrical key antenna assembly (front floor).

        When the electrical key transmitter is at the inspection point, check that the wireless door lock buzzer sounds.

        OK
        Wireless door lock buzzer sounds.

    NG

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)

    OK

    END (NO. 1 INDOOR ELECTRICAL KEY ANTENNA ASSEMBLY IS DEFECTIVE)

  9. CHECK HARNESS AND CONNECTOR (NO. 2 INDOOR ELECTRICAL KEY ANTENNA - CERTIFICATION ECU)


    1. Disconnect the P8 No. 2 indoor electrical key antenna assembly (rear floor) connector.

    2. Disconnect the H143 certification ECU (smart key ECU assembly) connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      P8-1 (CLG4) - H143-24 (CLG6) Always Below 1 Ω
      P8-3 (CLGB) - H143-25 (CG6B) Always Below 1 Ω
      P8-1 (CLG4) or H143-24 (CLG6) - Body ground Always 10 kΩ or higher
      P8-3 (CLGB) or H143-25 (CG6B) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  10. CHECK CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) (OUTPUT TO NO. 2 INDOOR ELECTRICAL KEY ANTENNA [REAR FLOOR])


    1. A003XFAE14
      Text in Illustration
      *1 Waveform
      *a

      Front view of wire harness connector

      (to No. 2 indoor Electrical Key Antenna [Rear Floor])
      *b Door open
      *c After approximately 30 seconds from when the door is closed

      Disconnect the P8 No. 2 indoor electrical key antenna assembly (rear floor) connector.

    2. Reconnect the H143 certification ECU (smart key ECU assembly) connector.

    3. Using an oscilloscope, check the waveform.

      OK
      Tester Connection Switch Condition Tool Setting Specified Condition
      P8-1 (CLG4) - P8-3 (CLGB)

      Procedure:


      1. Power switch off

      2. Door is open

      3. Door is closed

      4. 30 seconds elapse

      		 2 V/DIV., 500 ms/DIV. Pulse generation (See waveform)

    NG

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)

    OK

  11. REPLACE NO. 2 INDOOR ELECTRICAL KEY ANTENNA ASSEMBLY (REAR FLOOR)


    1. Temporarily replace the No. 2 indoor electrical key antenna assembly (rear floor) with a new or normally functioning one Click here.


    NEXT

  12. CHECK ELECTRICAL KEY ANTENNA IN KEY DIAGNOSTIC MODE


    1. Check the following antenna in the key diagnostic mode Click here.


      1. A003WGGE01
        Text in Illustration
        *a Inspection Point

        Check the No. 2 indoor electrical key antenna assembly (rear floor).

        When the electrical key transmitter is at the inspection point, check that the wireless door lock buzzer sounds.

        OK
        Wireless door lock buzzer sounds.

    NG

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)

    OK

    END (NO. 2 INDOOR ELECTRICAL KEY ANTENNA ASSEMBLY WAS DEFECTIVE)

  13. CHECK HARNESS AND CONNECTOR (NO. 3 INDOOR ELECTRICAL KEY ANTENNA - CERTIFICATION ECU)


    1. Disconnect the Q12 No. 3 indoor electrical key antenna assembly (inside luggage) connector.

    2. Disconnect the H143 certification ECU (smart key ECU assembly) connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      Q12-1 (CLG6) - H143-26 (CLG7) Always Below 1 Ω
      Q12-3 (CLGB) - H143-27 (CG7B) Always Below 1 Ω
      Q12-1 (CLG6) or H143-26 (CLG7) - Body ground Always 10 kΩ or higher
      Q12-3 (CLGB) or H143-27 (CG7B) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  14. CHECK CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) (OUTPUT TO INDOOR NO. 3 ELECTRICAL KEY ANTENNA)


    1. A003XFAE13
      Text in Illustration
      *1 Waveform
      *a

      Front view of wire harness connector

      (to No. 3 indoor Electrical Key Antenna [Rear Floor])
      *b Door open
      *c After approximately 30 seconds from when the door is closed

      Disconnect the Q12 No. 3 indoor electrical key antenna assembly (inside luggage) connector.

    2. Reconnect the H143 certification ECU (smart key ECU assembly) connector.

    3. Using an oscilloscope, check the waveform.

      OK
      Tester Connection Switch Condition Tool Setting Specified Condition
      Q12-1 (CLG6) - Q12-3 (CLGB)

      Procedure:


      1. Power switch off

      2. Door is open

      3. Door is closed

      4. 30 seconds elapse

      		 2 V/DIV., 500 ms/DIV. Pulse generation (See waveform)

    NG

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)

    OK

  15. REPLACE NO. 3 INDOOR ELECTRICAL KEY ANTENNA ASSEMBLY (INSIDE LUGGAGE)


    1. Temporarily replace the No. 3 indoor electrical key antenna assembly (inside luggage) with a new or normally functioning one Click here.


    NEXT

  16. CHECK ELECTRICAL KEY ANTENNA IN KEY DIAGNOSTIC MODE


    1. Check the following antenna in the key diagnostic mode Click here.


      1. A003VIDE01
        Text in Illustration
        *a Inspection Point

        Check the No. 3 indoor electrical key antenna assembly (inside luggage).

        When the electrical key transmitter is at the inspection point, check that the wireless door lock buzzer sounds.

        OK
        Wireless door lock buzzer sounds.

    NG

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)

    OK

    END (NO. 3 INDOOR ELECTRICAL KEY ANTENNA ASSEMBLY WAS DEFECTIVE)