GPS Previous Destinations Keeps Deleting, Electrical/Battery Issue?

I'm new so not sure if I'm posting this in the correct forum.

Bought a used 2007 Gen II in 2009, and have since that time been very happy and had few issues.

However, lately I have noticed some problems that are very disruptive, and am concerned they may be indicating a bigger issue ahead.

I rely very heavily on the GPS, using it every time I drive. In the past few months, I have noticed that sometimes when I start the car, all of my "Previous Destinations" have completely disappeared, and it says "no previous destinations"! Which is insane, because I have been accumulating previous destinations for 6 years now! It is hugely disruptive for me to find these gone, because I reuse many a few times but don't want to save all of them to "My Places." Strangely, My Places are still there, not deleted. The deleted destinations never come back, and I have to painstakingly enter all my addresses again, which is difficult for me because of a disability. In the past few months, this has happened 3 or 4 times! When this happens, the region is also always reselected to zone 9, which I am not in (not sure if that's where the first owner lived?), so I always have to enter everything in all over again.

A few years ago I had to replace the 12V battery, and I can understand why I lost all my memory in that instance. But the battery should be fine.

I have also noticed a few other strange occurrences in the past few months, which may or may not be related. There are times when suddenly the key fob does not work, and I cannot get into the car. The battery is new, so it's not that. I was worried it might indicate an electrical problem, because also a few times now I have gone to start the car and it goes into battery mode instead of turning over - as in, the indicators and lights come up, but the car doesn't start. Fortunately, when I turn it off and start again it has resolved. A few other times, I have started the car and the buttons seem to be crossed - pressing Destination leads to Audio, pressing Menu leads to Map, etc. Again, fortunately I restarted the car and all buttons worked normally again. Same thing, once I started the car and the screen did not turn on at all, just stayed black. Restarted, and it was back on.

So I am wondering what these sudden destination deletions might mean in this context. I am very far away from a dealership, and can't afford a major work-up if it's not necessary. A few possibilities I considered are that the destination cache might zero out when I have not used the car for an extended period. I don't drive every day, and there are some times when I don't use the car for 2 weeks or a little more. I also live in a location by the ocean, and so I have wondered if perhaps the salt air is corroding my electronics. I have tried to rinse the underside of the cab with fresh water every few weeks, but other than that I don't know what I could do to prevent salt damage.

Maybe what's going on with the NAV is totally unrelated to these things, and can be solved simply in another way. I have no clue really what's going on. But I don't want to have to deal with this again. And, if there is reason to think a serious electrical or other problem might be imminent, I would like to know that so I can take care of it before the car gets totaled, because I'd really like to keep my Prius for a long time if I could!

Thanks for any help.

 

Wow, my apologies for disappearing! I got the flu right after I posted the question, and was in bed for most of the next two weeks. By the time I recovered, so many things had piled up I completely forgot that I posted this thread!

The reason I did not think it should be a 12v battery failure was because I just replaced the battery 2 years ago, with an Optima DS46B24R which was brand new, fully charged, and in excellent shape. The battery's warranty alone is for 3 years, and the battery should be expected to last a good deal longer than that! (I am however in a hot climate, plus have salty sea air, which might affect its life). Since that time I was driving decent distances on highways quite frequently, and saw no troubles. But when I think back, the other handful of times this GPS deletion has occurred, I think I also had not been able to drive for an extended period. I am dealing with a life-threatening illness, and so there are just times when I can't drive or attend to the car for a while, and then it gets regular use again. The periods of not turning on the car don't go beyond 2 weeks, but they have been a little more frequent this year due to illness complications.

To clear up the key fob issue, it seems that the new battery I put in was no good (I had it for about a year before opening it and using it), so I just replaced it with a brand new just-bought battery, and there are no more problems related to it.

I also have not had this GPS Previous Locations issue since I posted the thread - but then again, I did use the car at least once a week in that time. Now that I am not so sick, I am using it daily.

So I will still have to check out the state of the 12v, check the connectors, etc, and use the display screen to check its charge (I forget at the moment how to do that, but I'll look it up to remind me). If there is reason for concern, I will take the car in to the dealer to put in a new battery, and while doing so will have the rest of its systems checked out (I just wanted to avoid this for a while since all of my cash has gone to medical bills and I don't have extra for the car right now). If everything looks great with the battery though, and I don't even have to bother dealing with the warranty and all that, then possibly this is just a symptom of leaving the car for 2 weeks at a time, and so I have to try to find a new solution, like possibly asking a neighbor to turn the car over for me or something, if I don't want this to happen again during my worse times. The car may just be telling me it's feeling neglected and needs consistent attention!

I adore this car, and it has been relatively little trouble compared with other makes and models I have owned. Considering it is 8 years old and is approaching 100,000 miles, it has been doing quite well. I want to at least do the minimum to keep it running for a number of years longer! If it ran a whole other 8 years more, I would be thrilled! I don't really feel jealous of any other cars with this Prius, so I do want to do what's necessary to keep it going.

 

Thanks, I will look into that!