Hi i recently installed my D3... and its been working for about 2 weeks but today i was in the middle of a route and it went back to its original location when we first installed it in "hollywood, CA"... The unit recognizes "north" because the screen rotates, but it doesnt move forward or backward, just 360... Anyhelp? Is there a speed sensor wire that possibly got disconnected? Or a bad connection with my antenna? The antenna is in the front window and is viewable 360 to the sky, like i said the unit has worked for 2 weeks, it just goofed today?