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Section 368 (Body Control System - Diagnosis): Pre-Check

WARNING: This page is about a different car, the 2003 Lexus LX 470. However, it is still accessible from the selected car via links, so may be relevant.
  1. DIAGNOSIS SYSTEM 
    1. Description

      ECU data of this system can be read from DLC3 of the vehicle.

      Therefore when there seems to be a trouble on this system, use hand-held tester to check and troubleshoot it.

      Fig 1: Connecting Hand-Held Tester To DLC3
      G03375151Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Check the DLC3.

      The vehicle's ECM uses ISO 9141-2 for communication. The terminal arrangement of DLC3 complies with SAE J1962 and matches the ISO 9141-2 format.

    Fig 2: Identifying DLC3 Terminal
    G03375152Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    TERMINAL CONNECTION/SPECIFIED CONDITION

    Terminal No. Connection/Specified Condition Condition
    4 Chassis Ground <--> Body Ground/1 or less Always
    13 TC <--> Body Ground/9 - 14 V Always

    HINT:

    If the display shows "UNABLE TO CONNECT TO VEHICLE" when the cable of the hand-held tester is connected to DLC3, the ignition switch is turned ON and the hand-held tester is operated, there is a problem either on the vehicle side or the tool side.

    • If communication is normal when the tool is connected to another vehicle, inspect DLC3 on the original vehicle.
    • If communication does not function when the tool is connected to another vehicle, the problem is probably in the tool itself, so consult the Service Department listed in the tool's instruction manual.
  2. USING HAND-HELD TESTER 
    1. Hook up the hand-held tester to the DLC3.
    2. Monitor the ECU data by following the prompts on the tester screen.

    HINT:

    Hand-held tester has a "Snapshot" function which records the monitored data. Please refer to the hand-held tester operator's manual for further details.

  3. DTC CLEAR 

    DTC and the freeze frame data can be erased by operating the hand-held tester.

  4. DATA LIST 

    HINT:

    By the DATA LIST displayed on the hand-held tester, you can read the value of the switch, sensor, actuator and so on without removing any parts. Reading the DATA LIST as a first step of troubleshooting is one of the method to shorten the labor time.

    1. Connect the hand-held tester to DLC3.
    2. Turn the ignition switch ON.
    3. According to the display on tester, read the "DATA LIST".
      1. Body ECU (Main)

        Power source & ignition switch: 

        Terminal SPECIFIED CONDITION

        Item Measurement Item/Display (Range) Normal Condition Diagnostic Note
        ACC SW ACC SW signal ON: IG key is in ACC, ON or START position
        OFF: IG key is in OFF position        		 -
        IG SW IG SW signal ON: IG key is in ON or START position
        OFF: IG key is in OFF or ACC position        		 -

        Key unlock warning switch: 

        Terminals SPECIFIED CONDITION

        Item Measurement Item/Display (Range) Normal Condition Diagnostic Note
        KEY UNLOCK WRN SW Key unlock warning SW signal ON: Key is IG key cylinder
        OFF: Key is not in IG key cylinder        		 -

        Door courtesy switch: 

        Terminals SPECIFIED CONDITION

        Item Measurement Item/Display (Range) Normal Condition Diagnostic Note
        LUGG COURTSY SW Luggage compartment door's courtesy SW signal ON: Luggage door is open
        OFF: Luggage door is closed        		 -
        D DOR CTY SW Driver's door courtesy SW signal ON: Driver's door is open
        OFF: Driver's door is closed        		 -
        P DOR CTY SW Passenger's door courtesy SW signal ON: Passenger's door is open
        OFF: Passenger's door is closed        		 -
        Rr DOR CTY SW Rear door courtesy SW signal ON: Either right or left rear door is open
        OFF: Both the right and left doors are closed.        		 -

        Headlight dimmer switch: 

        Terminals SPECIFIED CONDITION

        Item Measurement Item/Display (Range) Normal Condition Diagnostic Note
        DIMMER SW Dimmer SW signal ON: Dimmer SW is on (High Beam) or High flasher SW is on
        OFF: Dimmer SW is OFF (Low Beam) and High flasher SW is off        		 -
        HIGH FLASHER SW High flasher SW signal ON: High flasher SW is on
        OFF: High flasher SW is off        		 -

        Light control switch: 

        Terminals SPECIFIED CONDITION

        Item Measurement Item/Display (Range) Normal Condition Diagnostic Note
        AUTO LIGHT SW Auto light SW signal ON: Light control SW is in Auto position
        OFF: Light control SW is in except Auto position        		 -
        HEAD LIGHT SW Head light SW signal ON: Light control SW is in HEAD position
        OFF: Light control SW is in except HEAD position        		 -
        TAIL LIGHT SW Taillight SW signal/ON ON: Light control SW is in TAIL or HEAD position
        OFF: Light control SW is in OFF or AUTO position        		 -
        TAIL CANCEL SW Tail cancel switch ON: Tail cancel switch is ON position
        OFF: Tail cancel switch is OFF position        		 -

        Door key lock and unlock switch: 

        Terminals SPECIFIED CONDITION

        Item Measurement Item/Display (Range) Normal Condition Diagnostic Note
        DOR KEY SW-LOCK Passenger or back Door key switch lock side ON: Passenger or back door key switch is lock position
        OFF: Passenger or back door key switch is unlock position        		 -
        P DOR KEY SW-UL Passenger or back door key switch unlock side ON: Passenger or back door key switch is unlock position
        OFF: Passenger or back door key switch is lock position        		 -
        P LOCK POS SW Passenger lock position switch ON: Passenger lock position switch is lock position
        OFF: Passenger lock position switch is unlock position        		 -
        Rr. LOCK POS SW Rear lock position switch ON: Rear lock position switch is lock position
        OFF: Rear lock position switch is unlock position        		 -
        D/L SW-LOCK Door lock switch lock side ON: Door lock switch is lock position
        OFF: Door lock switch is unlock position        		 -
        D/L SW-UNLOCK Door lock switch unlock side ON: Door lock switch is unlock position
        OFF: Door lock switch is lock position        		 -

        Parking brake switch: 

        Terminals SPECIFIED CONDITION

        Item Measurement Item/Display (Range) Normal Condition Diagnostic Note
        PARKING BRAKE SW Parking brake switch ON: Parking brake switch is ON position
        OFF: Parking brake switch is OFF position        		 -

        Driver seat buckle switch : 

        Terminals SPECIFIED CONDITION

        Item Measurement Item/Display (Range) Normal Condition Diagnostic Note
        D SEAT BUCKL SW Driver seat buckle switch ON: Driver seat buckle switch is ON position
        OFF: Driver seat buckle switch is OFF position        		 -

        Seat memory switch: 

        Terminals SPECIFIED CONDITION

        Item Measurement Item/Display (Range) Normal Condition Diagnostic Note
        SEAT M1 SW Sear memory switch 1 ON: Seat memory switch 1 is ON position
        OFF: Seat memory switch 1 is OFF position        		 -
        SEAT M2 SW Sear memory switch 2 ON: Seat memory switch 2 is ON position
        OFF: Seat memory switch 2 is OFF position        		 -
        SEAT SET SW Sear set switch ON: Seat set switch is ON position
        OFF: Seat set switch is OFF position        		 -

        DRL relay circuit: 

        Terminals SPECIFIED CONDITION

        Item Measurement Item/Display (Range) Normal Condition Diagnostic Note
        DRL FUNCTION DRL function ON: DRL is ON position
        OFF: DRL is OFF position        		 -

        Door lock control: 

        Terminals SPECIFIED CONDITION

        Item Measurement Item/Display (Range) Normal Condition Diagnostic Note
        AUTO LOCK Vehicle speed sensing auto lock function ON: Vehicle speed sensing auto lock is ON
        OFF: Vehicle speed sensing auto lock is OFF        		 -
        UNLK/KEY TWICE Unlock w/ 2 times D key operation ON: Unlock w/ 2 times D key operation is ON position
        OFF: Unlock w/ 2 times D key operation is OFF position        		 -
        ALL UNLK/OPN-CL All Unlock w/ D door open-close ON: All Unlock w/ D door open-close is ON position
        OFF: All Unlock w/ D door open-close is OFF position        		 -
        Terminals SPECIFIED CONDITION

        UNLOCK/PARK Unlock w/ IG ON, shift P, speed 0 ON: Unlock w/ IG ON, shift P, speed is ON position
        OFF: Unlock w/ IG ON, shift P, speed is OFF position        		 -
        AUTO LOCK/SHIFT Auto Lock/shift not P ON: Auto Lock/shift not P is ON position
        OFF: Auto Lock/shift not P is OFF position        		 -

        Wireless door lock control: 

        Terminals SPECIFIED CONDITION

        Item Measurement Item/Display (Range) Normal Condition Diagnostic Note
        WIRELESS OPER Wireless door lock control function ON: Wireless door lock control function
        OFF: Wireless door lock control does not function        		 -
        HAZARD ANS BACK Hazard answer back of the wireless ON: Hazard answer back of the wireless is ON position
        OFF: Hazard answer back of the wireless is OFF position        		 -

        Wireless door lock buzzer: 

        Terminals SPECIFIED CONDITION

        Item Measurement Item/Display (Range) Normal Condition Diagnostic Note
        WIRELESS BUZZ VOL Wireless door lock buzzer volume OFF/MIN/MID3/MID2/MID1/MAX -
        DOWN/WIRELESS P/W DOWN W/ transmitter ON: P/W DOWN W/ transmitter ON position
        OFF: P/W DOWN W/ transmitter OFF position        		 -
        AUTO LOCK DELAY Auto lock time 30 s./60 s. -
        UNLOCK/2 OPER 2 times operation wireless unlock ON: 2 times operation wireless unlock is ON position
        OFF: 2 times operation wireless unlock is OFF position        		 -
        ALARM FUNCTION Panic function ON: Panic function is ON position
        OFF: Panic function is OFF position        		 -
        OPEN DOOR WARN Open door warning buzzer ON: Open door warning buzzer is ON
        OFF: Open door warning buzzer is OFF        		 -

        Light control sensor: 

        Terminals SPECIFIED CONDITION

        Item Measurement Item/Display (Range) Normal Condition Diagnostic Note
        ILLUMINATE RATE Illumination rate information - -

        Illumination: 

        Terminals SPECIFIED CONDITION

        Item Measurement Item/Display (Range) Normal Condition Diagnostic Note
        LIGHTING TIME Lighting time 7.5s./15s./30s. -
        ILLUMI SYSTEM Operation of illumination system ON: Illumination is ON position
        OFF: Illumination is OFF position        		 -
        LIGHT CONTROL Light control condition of illumination system ON: Illumination system is ON
        OFF: Illumination system is OFF        		 -
        I/L ON/ACC OFF Light the I/L when ACC OFF ON: Light the I/L when ACC OFF is ON position
        OFF: Light the I/L when ACC OFF is OFF position        		 -
        I/L ON/UNLOCK Interior light ON w/unlock ON: Interior light ON w/unlock is ON position
        OFF: Interior light ON w/unlock is OFF position        		 -
        RESPONSE TIME Response time 0.1 s./1.0s. -

        Park/Neutral position switch: 

        Terminals SPECIFIED CONDITION

        Item Measurement Item/Display (Range) Normal Condition Diagnostic Note
        P/N POS SW P/N position switch ON: Sift is P position
        OFF: Sift is except P position        		 -

        Alternator signal: 

        Terminals SPECIFIED CONDITION

        Item Measurement Item/Display (Range) Normal Condition Diagnostic Note
        ALT L SIG Alternator L terminal ON: Input voltage is 2.0 or 6.0 V
        OFF: No voltage        		 -

        Others: 

        Terminals SPECIFIED CONDITION

        Item Measurement Item/Display (Range) Normal Condition Diagnostic Note
        SENSITIVITY Turn on luminous intensity DARK2/DARK1/NORMAL/LIGHT1/LIGHT2 -
        LIGHT OFF DELAY Light auto OFF delay OFF/30 s./60 s./90s. -
        DISP EX ON SEN Display extinction luminous intensity DARK2/DARK1/NORMAL/LIGHT1/LIGHT2 -
        DISP EX OFF SEN Display extinction re-leaseluminousintensity DARK2/DARK1/NORMAL/LIGHT1/LIGHT2 -
      2. Body ECU (Sub)

        Power source & ignition switch: 

        Terminals SPECIFIED CONDITION

        Item Measurement Item/Display (Range) Normal Condition Diagnostic Note
        IG SW IG SW signal ON: IG key is in ON or START position
        OFF: IG key is in OFF or ACC position        		 -

        Park/Neutral position switch: 

        Terminals SPECIFIED CONDITION

        Item Measurement Item/Display (Range) Normal Condition Diagnostic Note
        P/N POS SW P/N position switch ON: Sift is R position
        OFF: Sift is except R position        		 -

        Wiper switch: 

        Terminals SPECIFIED CONDITION

        Item Measurement Item/Display (Range) Normal Condition Diagnostic Note
        WIPER SW (SM) S/M terminal (front wiper position) of wiper switch ON: Front wiper is except stop position
        OFF: Front wiper is stop position        		 -
        R-LINKED WIPER Reverse linked wiper function ON: Front wiper switch ON and shift lever R OFF:- -
  5. ACTIVE TEST 

    HINT:

    Performing the ACTIVE TEST using the hand-held tester allows the relay, VSV, actuator and so on to operate without parts removal. Performing the ACTIVE TEST as a first step of troubleshooting is one of the method to shorten the labor time.

    It is possible to display the DATA LIST during the ACTIVE TEST.

    1. Connect the hand-held tester to the DLC3.
    2. Turn the ignition switch ON.
    3. According to the display on tester, perform the "ACTIVE TEST".
      1. Body ECU (Main)
        ACTIVE TEST

        Item Test Details Diagnostic Note
        HAZARD Turns Hazard light flasher relay ON/OFF -
        BUZZ CONT SOUND Wireless buzzer ON/OFF -
        BUZZ RESP SOUND Wireless buzzer ON/OFF -
        HEAD LIGHT Turns Head light relay ON/OFF -
        HEAD LIGHT (HI) Turns Head light relay ON/OFF -
        TAIL LIGHT Turns Tail light relay ON/OFF -
        DRL RLY (Test Details) Turns DRL relay ON/OFF (Vehicle Condition) IG SW is ON, Engine is stopped and Light control SW is in OFF position. -
        DIMMER SIG Turns auto dimmer ON/OFF -
        ILLUMI OUTPUT (Test Details) Turns Interior light and Key illumination ON/OFF (Vehicle Condition) Interior light SW is in Door position -
        OPN DOR WRN LGT Open door warning light ON/OFF -
        P P/W UP/DOWN Passenger power window UP/DOWN -
        RL P/W UP/DOWN RL power window UP/DOWN -
        RR P/W UP/DOWN RR power window UP/DOWN -
        R ROOM LIGHT Rear room light ON/OFF -
        DOOM RLY CUT Doom light ON/OFF -
        DOOR LOCK Drive the Door lock motor at all doors LOCK/UNLOCK -
      2. Body ECU (Sub)
        DIAGNOSTIC NOTE

        Item Test Details Diagnostic Note
        CONSOLE LIGHT Center console light ON/OFF -
        STEP LIGHT Side step light and outer foot light ON/OFF IG = NO key and all doors are locked
        R WIPER MOT Rear wiper motor ON/OFF -
        SCUFF PLATE LEG Foot light and inside door handle illumination ON/OFF -
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