I too have a Garmin 60CSx and it is operating like the day I bought it. I'm still running it on alkaline batteries, will switch to NiMH next battery change. Make sure the correct battery is selected in the set-up menu and that you are not using lithium primary batteries. The 60CSx is not designed to handle lithium primary batteries.

Other than that, it's an electronic devise and while some may go on forever, others will fail earlier. The Garmin GPS V that I've had since 2002 still works.