Welcome to JustAnswer !! I am Andy and I will be glad to help you out with your issue today.
First connect the GPS to your computer using the cable that came with it. Then see if it makes any difference. If it does, then you know that car charger has issues or the car plug isnt giving right output.
Since the operating system and navigation software are preloaded into the internal flash memory of the GPS, the freezing may either be software or hardware failure.
First, press the "Reset" button or push the stylus into the "Reset" hole, to see if the navigation software can load successfully.
[Reference : Nextar]
If the program still does not load, then the software may be corrupted. Also, if the internal memory fails to read or write and the software cannot load properly, it may be caused by hardware failure.
Nextar no longer provides support for its products in US region and so the only option you have is to buy a new gps unit. I would recommend a Tomtom or Garmin.
Feel free to ask any question or concern you may have. I will be glad to help you.
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