Navigation Symptom Diagnosis (With Navigation)

Certain circumstances and system limitations may result in occasional vehicle positioning errors. Some clients may think this indicates a problem with the navigation function when, in fact, the system is normal. Keep the following items in mind when interviewing clients about symptoms of the navigation function.

Self-Inertial Navigation Limitations 

The limitations of the self-inertial portion of the navigation function (the gyro and the vehicle speed signal) can cause discrepancies between the vehicle's actual position and the indicated vehicle's position (GPS vehicle position).

The following circumstances may cause vehicle positioning errors:

• Moving the vehicle with the engine stopped and the vehicle stopped, such as by ferry or tow truck, or if the vehicle is spun on a turn table.
• Tire slippage, changes in tire rolling diameters, and some driving situations may cause discrepancies in travel distances. Examples of this include;
  1. -

     Continuous tire slippage on a slippery surface

  2. -

     Driving with snow chains mounted

  3. -

     Abnormal tire pressure

  4. -

     Incorrect tire size

  5. -

     Frequent lane changes across a wide highway

  6. -

     Very bumpy roads

• Tolerances in the system and map inaccuracies sometimes limit how precisely the vehicle's position is indicated. Examples of this include;
  1. -

     Driving on roads not shown on the map (map matching is not possible)

  2. -

     Driving on a road that winds in one direction, such as a loop bridge, an interchange, or a spiral parking garage

  3. -

     Driving on a road with a series of sharp hair-pin turns

  4. -

     Driving near a gradual highway exit or transition

  5. -

     Driving on one of two close parallel roads

  6. -

     Making many 90 degree turns

System Initialization 

If the infotainment control unit loses power (like the 12 volt battery was disconnected), the system requires initialization.

This initialization requires the following:

• Press and hold the AUDIO POWER ( ) button for at least 2 seconds. The infotainment control unit exits the anti-theft mode. Or you can enter the 5-digit anti-theft code.
• GPS initialization (may not be needed depending of the length of time the system was without power).
• Map matching aligns the GPS to a location on the map.

GPS Initialization 

Depending on the length of time the 12 volt battery was disconnected, your system may require GPS initialization.

Map Matching 

This part of the initialization matches the GPS coordinates with a road on the map screen. To do this part of the procedure, make sure that the navigation system displays a map, and drive the vehicle on a mapped road shown on the map screen. Do not enter a destination at this time. When the name of the current road you are driving on appears at the upper of the screen, the entire procedure is complete. Your system is now ready to use.