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System Normal Condition Check

  1. CHECK SYSTEM NORMAL CONDITION 
    1. If the symptom is applicable to any of the following, it is intended behavior, and not a malfunction.
      PROBLEM SYMPTOM CHART

      Symptom Answer
      A longer route than expected is chosen. Depending on road conditions, navigation ECU may determine that a longer route is quicker.
      Even when distance priority is high, shortest route is not shown. Some paths may not be advised due to safety concerns.
      When vehicle is put into motion immediately after engine starts, navigation system deviates from actual position. If the vehicle is moved before the navigation system activates, system may not react.
      When running on certain types of roads, especially new roads, vehicle position deviates from actual position. When vehicle is driving on new roads not available on map disc, system attempts to match it to another nearby road, causing position mark to deviate.
    2. The following symptoms are not a malfunction, but are caused by errors inherent in the GPS, gyro sensor, speed sensor, and navigation ECU.
      1. The current position mark may be displayed on a nearby parallel road.
        Fig 1: Identifying Vehicle Position (Parallel Road)
        G05293196Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      2. Immediately after a fork in the road, the current vehicle position mark may be displayed on the wrong road.
        Fig 2: Identifying Vehicle Position (Fork In Road)
        G05293197Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      3. When the vehicle turns right or left at an intersection, the current vehicle position mark may be displayed on a nearby parallel road.
        Fig 3: Identifying Vehicle Position (Parallel Road)
        G05293198Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      4. When the vehicle is carried, such as on a ferry, and the vehicle itself is not running, the current vehicle position mark may be displayed in the position where the vehicle was until a measurement can be performed by the GPS.
        Fig 4: Identifying Vehicle Position (When Vehicle Carried)
        G05293199Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      5. When the vehicle runs on a steep hill, the current vehicle position mark may deviate from the correct position.
        Fig 5: Identifying Vehicle Position (When Vehicle Runs On Steep Hill)
        G05293200Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      6. When the vehicle makes a continuous turn of 360, 720, 1,080, etc. degrees, the current vehicle position mark may deviate from the correct position.
        Fig 6: Identifying Vehicle Position (When Vehicle Makes Continuous Turn)
        G05293201Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      7. When the vehicle moves erratically, such as constant lane changes, the current vehicle position mark may deviate from the correct position.
        Fig 7: Identifying Vehicle Position (When Vehicle Moves Erratically)
        G05293202Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      8. When the turn the ignition switch ACC or OFF position on a turn table before parking, the current vehicle position mark may not point in the correct direction. The same will occur when the vehicle comes out of parking.
        Fig 8: Identifying Vehicle Position (When Ignition Switch Turned To ACC Or ON Position)
        G05293203Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      9. When the vehicle is running on a snowy road, on a mountain path with the chains installed, or with a spare tire, the current vehicle position mark may deviate from the correct position.
        Fig 9: Identifying Vehicle Position (When Vehicle Runs On Snowy Road Or Mountain Path)
        G05293204Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      10. When a tire is changed, the current vehicle position mark may deviate from the correct position.

        HINT:

        • The diameter of the tire may change, causing a speed sensor error.
        • Performing the tire change in calibration mode will allow the system to correct the current vehicle position faster.
          Fig 10: Identifying Vehicle Position (When Tire Changed)
          G05293205Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002