BeanBR

The red light stopped working on my "spare" key. Put in new batteries just to make sure and still no light. No big deal, the key works fine.

Anyway, wanted to know if anyone has had this issue and had it fixed. Looks like something that would cost 10 bucks to do at any automotive locksmith but want to make sure there aren't any substantial risk of screwing up the key and then getting myself screwed by MB.

Nice Ride

Possibly you changed the setting from RF to IR? With car thefts up in NY, thieves can easily scan RF signal and take your car in 1 min. There is a way to turn of RF, possibly thats what happen to you.

Quenthel

Not sure if you are still on warranty and if the warranty terms are similar between yours and mine, but when my key started acting up and began consuming one battery every two weeks, it was replaced under factory warranty.