battery goes dead in about 2-3 hours. brand new battery, key is off.

You can start by putting a "test light" between the "negative" battery post and the negative cable. Using the alligator clip, put it on the post and the test light on the cable. This after the cable is removed. If the test light "lights up" you have a draw. Start by removing each fuse, one at a time. Pull the fuse out and if it stays lit, put the fuse back. Keep doing that till the light goes out. Look at your owner's manual to see the fuse layout. If you have an amp meter, that would be better... http://www.wikihow.com/Find-a-Parasitic-Battery-Drain

Parasitic loads are common. Could be an electric seat motor, alternator, etc. Need to check the circuits with fuses and see which one is drawing the power, then make the repairs. GL