do you have the valet key? it could be something with the key, if you have the other key be sure to use it as it will keep it charged. if you have the valet key use that for awhile and see if it does it at all. (i switch which key i use on a weekly basis, well at least i try to)

two keys (~250$) and the mechanism in the steering wheel for reading the keys will run near ~800$-1000$ at a dealer.

__________________