"brake" light comes on when cold
 

well within the past couple weeks, ive noticed that when its been colder, like freezing or below maybe, my red "brake" light comes on. sometimes when i start the car its there, sometimes it shows up while driving. and occasionally it will go away and sometimes come back. all braking and driving is perfectly fine. ebrake seems to work fine too. not really sure where to start looking since everything is working ok. any chance it could just be a sensor acting up with the temp? any suggestions would be apreciated. thanks.

usually means that air is in the brake lines, you should probably check your master cylinder and see how high the fluid is and bleed your brakes just to be safe.

I dont think that light will detect that you have AIR in your lines.. all it does is check the fluid level in the resevoir. Sensor is acting up.

well ill check the fluid level, and check to make sure theres no leaks or anything like that. know where the sensor is located and what it looks like?

Had a similar problem with my moms GP. Something with a sensor, and had to do with her parking brake. Can't remember exactly.

i know since my brother installed all new rotors and pads a couple years ago, the ebrake has been fairly loose. i mean it holds, but you can pull the handle all the way up with out too much effort. ill just double check everything tho.

Brake fluid, like any other fluid, contracts (takes up less volume) when cold. The colder it gets, the less volume it takes up. (Yes, I know water is weird in this instance!!) Now, if you are AT, or very near the low mark, it could be that the extreme cold makes the volume just low enough to set off the sensor. Or course, when you use your brakes, you heat up the fluid, and the level will rise a tiny bit. The first thing I would do, is just check your fluid level. It could be other things like a sticky brake light switch, air in the lines, but I'd first off insure the fluid level is okay.

ya, brake fluid is one of the ones i dont check frequently like i should. ill check over everything when it gets light out, since i forgot to today.