2009 Lexus SC 430 Navigation Manual - Page 10

BASIC FUNCTIONS Orientation of the map You can change the orientation of the map from North−up to Heading−up by touching the orientation symbol at the top left of the screen. Touch or . Limitations of the navigation system This navigation system calculates the current vehicle position using satellite signals, various vehicle signals, map data, etc. However, the accurate position may not be shown depending on the satellite condition, road configuration, vehicle condition or other circumstances. The Global Positioning System (GPS) developed and operated by the U.S. Department of Defense provides an accurate current vehicle position, normally using 4 or more satellites, and in some cases 3 satellites. The GPS system has a certain level of inaccuracy. While the navigation system will compensate for this most of the time, occasional positioning errors of up to 300 feet (100 m) can and should be expected. Generally, position errors will be corrected within a few seconds. North−up screen Heading−up screen North−up symbol Regardless of the direction of vehicle travel, North is always up. Heading−up symbol The direction of vehicle travel is always up. A red arrow indicates North. 28