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Section 298 (LEXUS Navigation System - Diagnosis): Pre-Check

WARNING: This page is about a different car, the 2004 Lexus SC 430. However, it is still accessible from the selected car via links, so may be relevant.
  1. USER TROUBLES UNDER NORMAL CONDITION OF THE NAVIGATION SYSTEM 
    1. Voice guidance is not performed even though the system is in normal condition when:
      1. The destination is not set up.
      2. The vehicle is not driving on the set route. (The remaining distance is not displayed at the lower left of the map screen that tells the current position of the vehicle.)
      3. "Guidance in Other Modes" is not set up. (In this case no voice guidance is given except on the map screen.)
    2. The vehicle icon turns around arbitrarily on the screen even when the system is in normal condition. If the ignition switch is turned to "ACC" or "ON" while the vehicle is turning around such as being on the turntable, the Navigation System memorizes the angle speed of that moment as the standard figure. To solve this problem, at the vehicle speed of 0 MPH (0 km/h), turn off the ignition switch and, then turn it to "ACC" or "ON" again, and see whether any trouble occurs again.
  2. INSPECTION OF THE LOCATION WITH TROUBLE OCCURRENCE 
    1. Examine whether the wrong display of the vehicle icon appears in a certain location or in several locations.

      HINT:

      It is difficult to determine the accurate vehicle position when driving on a freeway, a looped road or a road which runs in parallel with another, and immediately after going out of the parking area. In such cases the vehicle icon can be displayed off the real position of the vehicle.

  3. OUTLINE OF AVC-LAN 
    1. Each unit of the LEXUS navigation system connected with AVC-LAN (communication bus) transmits a signal of each switch. When +B short or GND short occurs in this AVC-LAN, the LEXUS navigation system will not function normally as the communication is discontinued. In this AVC-LAN, the radio and player becomes the master of the communication, having a resistance necessary for transmitting the signals.
      Fig 1: AVC-LAN Component Block Diagram
      G01449592Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  4. CELLULAR MOBILE PHONE (Option) 
    1. Characteristics of Cellular Mobile Phone
      Fig 2: Phenomena/Cause Table
      G01449593Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      HINT:

      *"Preparation for sending out radio waves" has the following process.

      Picking up the receiver (turning on the phone switch) sends out the dial signal to the Radio Circuit Control Center.

      The center chooses the radio base of the highest-sensitivity in receiving the dial signal. It also makes a telecommunication circuit by choosing a vacant channel out of many.

      This process is called "Preparation for Sending out Radio Waves".

    2. Before troubleshooting, check the following points:
      1. Troubles should be checked where the cellular mobile phone can receive enough radio wave.
      2. Troubles occur even with different cellular mobile phones (even with different telephone companies, if possible).
      3. Battery life of the cellular mobile phone and its recharge state must be in good condition.
      4. The antenna of the cellular mobile phone should be stuck out.
      5. Troubles occur even when the cellular mobile phone is formatted.

      HINT:

      • When it is formatted, the data and the registration of telephone numbers in the cellular mobile phone will be deleted.
      • The member ID and the password need to be reentered.
  5. DIAGNOSIS SYSTEM MODE 

    HINT:

    Diagnosis System Mode is operated as follows. (See Fig 3.)

    Fig 3: Diagnosis System Mode Display Chart
    G01449594Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  6. SERVICE CHECK MODE 

    HINT:

    Since Check Mode is operated as follows. (See Fig 4.)

    Fig 4: Service Check Mode Display Chart
    G01449595Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  7. DISPLAY CHECK MODE 

    HINT:

    Display Check Mode is operated as follows. (See Fig 5.)

    Fig 5: Display Check Mode Display Chart
    G01449596Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  8. NAVIGATION CHECK MODE 

    HINT:

    Navigation Check Mode is operated as follows. (See Fig 6.)

    Fig 6: Navigation Check Mode Display Chart
    G01449597Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  9. START-UP AND FINISHING OF THE DIAGNOSIS 
    1. Diagnosis Start-up by touch switch.
      1. Vehicle speed should be 0 km/h (0 mph).
      2. Apply the parking brake.
      3. Turn the ignition switch to ACC or ON.
      4. Push the DISPLAY button.
      5. Activate the screen adjustment screen.
      6. Alternately touch the upper and lower bottom parts of the left end of the screen 3 times respectively.
        Fig 7: Locating Display Button
        G01449598Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

        HINT:

        Before starting the Diagnosis System, make sure that the map appears on the screen after turning on the IG switch.

        If not, some items cannot be checked.

        Fig 8: Display/Description Table
        G01449599Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

        HINT:

        • When Diagnosis System starts, Service Check screen is displayed and the service check begins.
        • Select MENU to display Diagnosis Check Menu.
    2. Finishing the Diagnosis System

      Turn the ignition switch off to finish the mode.

      Fig 9: Locating Concealed Touch Switch On Scan Tool Display
      G01449600Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  10. SERVICE CHECK MODE 
    1. Service Check
      1. Start the Diagnosis System.
        Fig 10: Scan Tool Display Explanation Table
        G01449601Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
        Fig 11: Identifying Check Mode Functions On Scan Tool Display
        G01449602Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

        HINT:

        Service Check displays the check results based on the information obtained from each component's response to "System Check Execution" and "Diagnosis Memory Request", and the information of "Current DTC Notification" (the Unit Check and the LAN Check information will be displayed on the next screens.).

      2. Read Check Result
        Fig 12: Check Result/Meaning Table
        G01449603Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

        HINT:

        • After repair and check, press "Code CLR" for more than 3 sec. to delete diagnosis memory.
        • After deleting diagnosis memory, press "Recheck" and make sure "OK" is displayed on the screen.
      3. "EXCH", "CHEK" and "Old" can be used as switches to activate "LAN Check Mode" and "Unit Check; for detail information. Check troubled parts of the components in these modes by referring to the DTC code list.
        Fig 13: Lan Check Mode Display Table
        G01449604Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
        Fig 14: Identifying Lan Check Mode Scan Tool Display
        G01449605Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
        Fig 15: Identifying Unit Check Mode Scan Tool Display
        G01449606Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      HINT:

      • Detecting Unit DTC activates the Unit Check Mode on the screen.
      • Detecting no LAN DTC activates the LAN Check Mode on the screen.
      • Use the displayed switch to change to the Unit Check Mode and the LAN Check Mode.
      • The LAN Check Mode chooses and displays the LAN DTC out of DTC of components identified as "CHEI the Service Check.
      • In the Unit Check Mode, DTC which is identified as "EXCH" in the Service Check, is displayed as classified into Current DTC and Past DTC.
  11. DISPLAY CHECK MODE 
    Fig 16: Display Check Mode Display Explanation Table
    G01449607Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    HINT:

    In Display Check Mode, above checks can be performed.

    Fig 17: Identifying Display Check Mode Scan Tool Display
    G01449608Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Display Color Bar Check
      1. Start the Diagnosis System.
      2. Select "MENU".
      3. Select "Display Check".
      4. Select "Color Bar Check".
      5. Make sure that each color name is corresponding to each color on the bar.

        HINT:

        Select Black, Red, Green, Blue, White and Stripe to display selected colors and stripe on the entire screen.

      6. Compare with the Color Bar Check in the Navigation Check and make sure that no difference is found.
        Fig 18: Identifying Color Bar Check Mode Scan Tool Display
        G01449609Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Display Touch Switch Check
      1. Start the Diagnosis system.
      2. Select "MENU".
      3. Select "Display Check".
      4. Select "Touch Switch Check".
      5. Touch the screen and make sure that every line reacts to the touch.

        HINT:

        After the Touch Switch Check for vertical lines, press "Next" to check horizontal lines.

        Fig 19: Identifying Touch Switch Check Mode Scan Tool Display
        G01449610Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Display Panel Switch Check
      1. Start the Diagnosis system.
      2. Select "MENU".
      3. Select "Display Check".
      4. Select "Panel Switch Check".
      5. Press each switch and make sure that it corresponds to the display on the screen.
        Fig 20: Panel Switch Check Display Description Table
        G01449611Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
        Fig 21: Identifying Panel Switch Check Scan Tool Display
        G01449612Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    4. Display Vehicle Signal Check
      1. Start the Diagnosis system.
      2. Select "MENU".
      3. Select "Display Check".
      4. Select "Vehicle Signal Check".
      5. Check the status of the vehicle signal (Battery, PKB, SPEED, TAIL) loaded into the display.

        HINT:

        Vehicle signal data is updated every 1 second.

        Fig 22: Identifying Vehicle Signal Check Mode Scan Tool Display
        G01449613Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  12. NAVIGATION CHECK MODE 
    Fig 23: Navigation Check Mode Description Display Table
    G01449614Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    Fig 24: "Menu" Display Item Meaning
    G01449615Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    HINT:

    • In the Navigation Check mode, the checks mentioned above can be conducted.
    • The Navigation ECU operates each Navigation Check screen.
      Fig 25: Identifying Navigation Check Scan Tool Display
      G01449616Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. GPS Information
      1. Start the Diagnosis system.
      2. Select "MENU".
      3. Select "Navigation Check".
      4. Select "GPS Information".
      5. Check the GPS-related information.
        Fig 26: GPS Display Description Table
        G01449617Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
        Fig 27: Identifying GPS Scan Tool Display
        G01449618Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Measurement Status: /*4 

      Fig 28: Measurement Status Display Explanation Table
      G01449619Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Status of Wave Reception: /*5 

      Fig 29: Status Of Wave Reception Display Explanation Table
      G01449620Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Vehicle Sensors
      1. Start the Diagnosis system.
      2. Select "MENU".
      3. Select "Navigation Check".
      4. Select "Vehicle sensors".
      5. Check the vehicle signals (ACC, REV, SPD) and the output signal of the gyro sensor introduced into the navigation ECU.
        Fig 30: Vehicle Sensors Display Explanation Table
        G01449621Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
        Fig 31: Identifying Vehicle Sensors Scan Tool Display
        G01449622Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Navigation Color Bar Check
      1. Start the Diagnosis system.
      2. Select "MENU".
      3. Select "Navigation Check".
      4. Select "Color Bar Check".
      5. Make sure that the set color matches the display color.
      6. Compare with the Color Bar Check in the Display Check and make sure that no difference is found.
        Fig 32: "Navi Menu" Display Table
        G01449623Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
        Fig 33: Identifying Navi Color Bar Check Scan Tool Display
        G01449624Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    4. Parts Information
      1. Start the Diagnosis system.
      2. Select "MENU".
      3. Select "Navigation Check".
      4. Select "Parts Information".
      5. Check the program and disc version.
        Fig 34: "Navi Item" Display Table
        G01449625Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
        Fig 35: Identifying Parts Information Scan Tool Display
        G01449626Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    5. Memory Copy/Paste

      HINT:

      This function is not available.

      Fig 36: "Navi Menu" Display Table
      G01449627Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      Fig 37: Identifying Memory Copy/Paste Scan Tool Display
      G01449628Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002