In my experience, the laser's battery life will gradually deteriorate over time if the switch is left in the on position. I would reccomend putting a new battery in it and making sure that the battery switch is left off when not in use. And, quit playing around with the laser once you get it sighted in!! I bought a gun (not a Kimber, but had CT grips on it) and fiddled around with the laser and always left the switch in the on position and experienced the same problem you are.
Hope this solves your problem!