Have any of you guys seen the navigation drop out and not know where you are at in my 06 Prius? Mine has done it twice in the last week.. when I go into the hidden screen I see only two or even One satellite locked on.... seems I need at least 3 for the nav to know where I'm at. Both times was around 4:00 or so in the eve. Once it lasted about an hour and a half, the last was only about 30 mins. Reboots etc do nothing when it happens.
Must be something to do with the seasons. Keep in mind that satellites do turn off twice a year (spring and fall equinox)... something about the sun is in direct path of the satellite and turning them off (or away anyway) protects the solar panels or something fragile on the satellite from burning and melting. You'll see missing weather satellite imagery as well because of this phenomenon. The exact details escape me at this moment.
When it did it this last time... me and my wife was trying to communicate on our cell phones and communication was terrible.... could be chance. Of course you never hear any of these vulnerabilities on the news. I'm just trying to rule out if its my car or satellite issues. When I got home this last time I pulled my wifes car out to see if hers was having trouble and it did not... of course I then looked at mine and I had about 5 satellites locked on.... who knows. When it happens I usually still track on longitude or latitude, just not both at the same time. For instance, it may track me going north, but loses me totally east and west and that setting stays where it last saw me. By the time it found me again the other day, it had followed me about 50 miles north and had me at the exact point, but was off by about 100 miles too far east "I was traveling west by NW."
For a position fix, one satellite will give your location as a sphere in space, two will produce a circle, three will give you two points. For good marine navigation, my GPS usually tracks eight to ten satellites. It's hard to do that on the ground, with trees and buildings in the way, but you need more than a couple of satellites. Most likely you were in an area with interference, multipath, or obstructions. Tom
It was areas I had traveled many times before.... so I don't Know... I don't know if there are sunspots that can interfere with all this or not... like I said, the second time I noticed cell reception was very terrible too and we we both in good locations. Just try to rule out problems with my nav.
There has been some recent solar activity, but it was on the far side of the sun, so I don't think it really affected us here.
guess it's kinda hard to repeat because every year it won't be on the exact date, it may be a day or two earlier/later than this year and stuff. Well if it doesn't occur again (again that assumes you drive through that area every day at the same time each day), then I'd say it's solar issues =P.
