Changing the electrics to work of the Ignition Switch

I would be interested to know if anyone has converted their car so that items such as the wipers, heater fan and indicators only work when the ignition is on.

Although I have yet to do it, the day will come when I leave the heater fan switched on and come back to a flat battery.

Can anyone advise?

It is a desirable thing to do and may be quite easy if the circuits you want to isolate this way can be easily rerouted at the back of the fuse box. However you will be changing the amount of current running through the switched supply and that means you need to check the fuse ratings and you will also be increasing the load on the switch. For both these reasons it may be better to isolate the power circuits you want switched and provide them with their own fuse and use a relay, powered from the ignition, to control it. I did the same thing for my headlights and now there are on their own circuit with separate fuses and relays to protect the switch.

I agree with Cosmo. Your idea is good, but from experience, the less that goes through the ignition switch, the better off you will be. Almost every Italian car that I have owned has, at some point, given problems with the ignition switch. When I've taken them apart the reason is generally the same - they get hot due to a poor connection and then things start to melt. When they melt, the connections get worse, and so on!

I can remember having fun scooting our old Fiat 500 through the centre of the town, standing on the rear bumper and holding on to the sunroof, while my wife sat in the driving seat, hoping that we wouldn't be seen by someone she knew......
A Fiat 128 coupe also had problems, but only in the starter position, and my Lancia Spyder seemed to go through more ignition switches than oil changes!