Turn off exterior lights in Ready, Prius Camping

Your car is 'configured' by Toyota in that way, probably due to local laws; most cars, including mine, have no lights when in 'ON' mode, even with engine running etc. I see your location, Reykjavik, may explain why; I also understand why you might need the heaters on overnight!

The first thing to do, is to check whether your local laws do actually require all those lights to be switched on, when the car is in on' mode. Then, to decide what to do next (it might be your car is from a Scandinavian country, imported; Volvos have running lights on all the time even in the UK!

Unless anyone knows how to reconfigure cars (which would be useful for many people but I don't think it has been cracked... yet...), it may be necessary to figure out a way to manually override the lights for camping mode. This would be possible and the wiring diagrams are available if needed; the risk would be that you would have to find a way to ensure the 'override' isn't accidentally left on when driving (or you could end up driving with no tail-lights in winter without realising)

 

In my Prius, there is a beep if the car is off, but I've left the headlights on; this is because the 12v battery is so small that the car *will* be dead if you leave them on when the car isn't powered up!

Did a quick bit of research around Iceland, and a website says : 'You are also required by law to always keep the car‘s headlights on. This is doubly important in winter when the days are short and dark.'

This would explain why the headlights come on and stay on. It is likely able to be reprogrammed, but I doubt anyone outside of Toyota currently has that knowledge. My Prius is New-Zealand new (not a used import). The benefits are that I get the display in English, but the downsides are that I can't switch it to miles per hour - that option is helpfully and permanently disabled by Toyota.

What I would do would be, first, to check what the law in Iceland says, in detail, about a car that is technically 'powered up' but which is parked in a designated parking place. Does a car in this situation have to have the lights switched on? If not, then it should be legal to disable the 'always-on' lights in a reversible manner, only when properly parked. You would have to read the actual legislation and even then there is always a risk (statutory law vs case law etc).

If, at this point, you still feel it is OK to disable the lights, it might be necessary to have a bank of switches that you can use to disable each of the lights that are 'on'; this would likely involve using relays for the higher-current lights, caution around ensuring proper fuses are used to prevent short circuits between the positive wire and any metal parts on the car, etc.

(actually, another option would be to check where the fuses are; I've never had to check on my Prius). On my Bluebird I could disable all those lights by pulling fuses, so I could just make modified fuses with switches dangling from the fuse box inside the cabin... This may be the way to go even if the fuses are in the engine bay (however... you would have to use thick wiring for the headlight switches, would have to ensure there are fuses to prevent problems with short circuits, and would have to keep a set of spare fuses to 'reverse' the modification if and when it fails (e.g. the switches will eventually wear out etc). You would need high-current fuses for the headlights for sure. I have done a similar modification on my 200SX where there is a kill-switch located somewhere very sneaky, and which has the entire 12v load (besides starter motor) running through it. It uses a high-current switch and worked well!

 

Any chance anyone has done modification to manually switch off lights for their gen 2 Prius?

I am facing this as well (I live in Finland), love camping in my Prius but need to be extra careful not to bother people with parking lights..