Exploring 500 died

My Explorist 500 just stopped working after years of good service. It failed to start on my last backtrail ride. It had worked fine several weeks prior. Is there a way to reset these little units? I always use while plugged in to ATV power outlet. If battery has gone bad will this stop unit from turning on even when using external power? Sure hope someone can help.

 

Thank you very much! You got me to thinking this could be the problem. I went on the search and found the small triple A adapter that came with the unit when new. Still in my headboard after I don't know how many years. Anyway, I removed the rechargeable battery that has been in the unit since new and installed 3 triple A's. Bingo! I have my unit back. So happy. This is just a little Explorist 500 but it was tweeked by a chap that used to be the Magellan service rep for all of Canada. He discovered the software on this little unit could be upgraded to a much more expensive and comprehensive unit. I was looking for him to help but unfortunately he was killed in a car accident 3 years ago. Thanks again for your suggestion.