System Normal Condition Check

If the symptom is applicable to any of the following, it is intended behavior, and not a malfunction.

SYSTEM NORMAL CONDITION CHECK

Symptom	Answer
A longer route than expected is chosen.	Depending on the road conditions, the navigation ECU may determine that a longer route is quicker.
Even when distance priority is high, the shortest route is not shown.	Some paths may not be advised due to safety concerns.
When the vehicle is put into motion immediately after the engine starts, the navigation system deviates from the actual position.	If the vehicle starts before the navigation system activates, the system may not react.
When running on certain types of roads, especially new roads, the vehicle position deviates from the actual position.	When the vehicle is driving on new roads not available on the map disc, the system attempts to match it to another nearby road, causing the position mark to deviate.

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: Displaying Current Position Mark On Nearby Parallel Road
  Courtesy 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: Displaying Current Vehicle Position Mark On Wrong Road
  Courtesy 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: Displaying Current Vehicle Position Mark On Nearby Parallel Road (When Vehicle Turns Right Or Left)
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
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 GPS.

Fig 4: Displaying Correct Position Of Vehicle When Carried
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
When the vehicle runs on a steep hill, the current vehicle position mark may deviate from the correct position.

Fig 5: Displaying Correct Position Of Vehicle When Runs On Sleep Hill
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
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: Displaying Correct Position Of Vehicle When Makes Continuous Turn Of 360, 720, 1,080 ETC Degrees
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
When the vehicle moves erratically, such as constant lane changes, the current vehicle position mark may deviate from the correct position.

Fig 7: Displaying Correct Position Of Vehicle When Constant Lane Changes
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
When the ignition switch is turned to the ACC or ON position on a turntable 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: Displaying Correct Position Of Vehicle When Turntable Before Parking
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
When the vehicle runs on the snowy road or a mountain path with the chains installed or using a spare tire, the current vehicle position mark may deviate from the correct position.

Fig 9: Displaying Correct Position Of Vehicle When Runs On Snowy Road Or Mountain Path
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
When a tire is changed, the current vehicle position mark may deviate from the correct position.

HINT:

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: Displaying Correct Position Of Vehicle When Tire Changed