Radiator Fan Switch Problems

[1slowdsm]

I've had my radiator fan connected from the radiator fan relay, on the passenger side, to a switch inside my car. Everytime I flick the switch my battery v would drop by about 2v, so it'll sit at 12.5ish then when I start driving it would jump up to 13.5ish. After a week or so I could see the drop go down to as low as 9v, which is about when my car would start losing battery power quickly. I've notice that my switch has been getting quite hot compared to what it was when I first added the switch.

NOW....the thing that bugs me is that every once in a while this would somewhat short out my battery - I would start driving and the car would just click on and off constantly for about 5seconds, then it would completely die. I would have to disconnect my battery, wait a bit and reconnect the battery and it would run fine again. This has happened twice to me since late August and I dont want to keep having to pull aside at any given time and disconnect the battery, it causes traffic and gets annoying.

Anyone have any ideas as to what's wrong so I can fix this before it gets too cold outside?