Can Sat Navs lose the plot

[factor-fiction]

My Sat Nav has been really useful until I left it for around 2 months without using it. But for the last few days it seems to have completely lost its bearings and has been of no use whatsover.

It finds the location I want but then starts to take me on a route that is clearly wrong. For very left turn it always now says turn left then turn right even there is no such right turn available so it starts saying 'turn around when possible' until it sorts itself out again. Also it tells me to turn left or right into someone's drive or a scrap yard when clearly it's not a through road.

I've tested it out over the last four days now and it's not getting any better

Has anyone else had this problem?

[Zeuhl]

Connect it up to its parent website via your computer and upgrade/reset it

[factor-fiction]

Thanks. It'sa TomTom.
Mine finds a signal and finds the location but just seems to give random instructions (eg come off motorway at a junction and then get back on). I'll look on the website- I thought you had to pay for updates but maybe there is something they can do such as reset to initial settings

[bushbaby_de]

It can go into demonstration mode (happened on a road trip with some friends) and it just sends you off somewhere totally random. There was something in the instructions book about how to get it out of demonstration mode and back into live mode.