Car laws (windshields, parking and naps)

I am off to Japan soon and for the first time I am hiring a car (previously I used bicycle and trains) as I want to drive around Chiba, Ibaraki, Gunma, Tochigi, Saitama (maybe not the last one too much).

I have my own Garmin GPS system which does have a Japanese map and locations of all the places I want to go and hotels. I have planned out routes so I spend the least amount of time on the road so I really want to use this. It's update with generally the most recent maps (although google maps taunts me with roads that aren't on the GPS).

However I know that most cars do have GPS systems built in around the centre console. So I want to know if there is any law which prohibits the attaching of a GPS unit to the windscreen (and the power cable that will hang down). I have tried to look on the internet aboiut this but have not found anything useful.

If I am legally parked am I allowed to nap in the car or will I get a policeman banging on the window? Ditto, I I visit a convience store and park in their carpark after buying food and drink am I likely to be chased off if I doze off in the car for a nap? I've seen people in cars and lorrys dozing from time to time so was just wondering.

Preferably attached gps on the dashboard not on windscreen, so as not to block the driver view.
Napping is no problem but doing it at conbini or business/private parking unless paid is not advisable.but if do so do park your car further from the entrance in order not to inconvenience actual customer ;-)

My GPS, when I use it, hangs on my windshield since it isn't attached to my car. I don't use it all the time, but I've also never had anyone tell me I can't use it like that. Just make sure it doesn't block your view.

People take naps in their cars all the time. There really aren't a lot of police around anyway (especially out in the country) so you don't really have to worry too much about it. Only thing is that sometimes they set up speed traps which are told on the radio that day, but as long as you're following all traffic laws you'll be fine.

I know all well but now I'm very tired XD
Wait until tomorrow night?

If yes I can make with images(simple illustrations)
especially about GPS and car/traffic laws.

Anyway read other basic traffic rules[PDF] storongly recommend
http://www.hkd.mlit.go.jp/topics/toukei/chousa/h20keikaku/e/e_all.pdf
after [P20] most pages are so.

Thanks for the replies, it is good to know that I can stick a GPS to the windscreen. I will try to put it on the dash but a lot of cars have no really good place to stick it down.

With convience stores being plentiful it will be easy to stop to check routes, eat, drink, use toilet and rest. I plan to travel around Japan and not use a single expressway as I see a lot more fun things that way.

Napping while legally parking is no problem at all, but most of the time, "idoling" in other words to keep the engine on is prohibited or at least not appreciated. Yet, not every parking lot is indoors.

Sure enough, a lot of professional drivers tend to and need to take naps at parking lots with air-conditioners on, but don't be surprised if someone tells you to turn off the engine.

Also, a lot of convenience stores have signs warning you to not "park for a long time."

In mid october it should be mild enough that I can live with aircon whilst the car is off. However I never let the engine idle as that is a waste of petrol.

I am sure convenience stores out in the sticks are less likely to care if I stay in the empty car park out the way in the dark. I remember cycling back home at 2am and seeing lorries and cars park with sleeping drivers in them.

Jamtex,

I hope you are saying that based on some kind of experience, but according to my experience as a frequent driver to Tochigi, in mid october, anywhere "in the sticks" in anywhere north than Tokyo gets quite chilly especially after the sun goes down. Either way, be sure you travel with a blanket or a sleeping bag.

Meanwhile, there are lesser 24/7 stores in the sticks. You can also sleep in Expressway "Parking Area"s though.

The last few times I have been to Ibaraki, Tochigi and Gunma come October it has been a pleasent 20c or so during the day. I know during the evening it does get colder as I remember requiring gloves as I cycled home.

However I plan to stay in hotels during this time. Although I plan to go to bed early and wake up early.