So I've had my car for about 8 months and the battery in my key is already dead... Is this common or just me?

 

Funny you should say that... I've gone through about 2 batteries in just over 2 years. My non keyless MB has been going 3 years on the original battery.
Maybe it's just a keyless thing.

 

I think that's normal. Apparently, the keyless go is always searching for car and thus uses up the battery quite a bit. I also heard that placing it around metal also depletes its life faster...not sure if there's any truth to this.

 

Yes they eat batteries at a fantastic rate, I got a 12 year old Tiburon still on the original fob battery, but it does not sound the same when started . Usually a fresh set very year to year and a half.

 

So . . . what happens when the battery dies - can't start the car? Are you left stranded?

 

Sounds about right. But only if the batteries are completely, completely dead.

Batteries should have some juice when it's running low, and a few gentle taps to the key fob should generate enough juice for you to start the car to drive to the nearest store that sells that battery.

Or just have a few spares in the car as someone suggested earlier.

 

I've been changing my keyfob batteries once a year for my keyless go. You'll be notified on your dash that the battery is low long before it goes dead.

 

The guys are correct the doors will usually still open but you will notice a diminished distance as the batteries get low and the car will tell you to replace them long before they go dead. But it is my understanding that if completely dead use the manual key to open the door and then insert the fob into the dash and turn key as in a other car. Keyless go will not work with dead batteries. Or get the other fob out of the wifes' purse

 

So I assume the car doesn't charge the key?

My previous bimmer was charging the key when it was inserted in the slot, which was nice. It was also telling me when the key's battery was low.

That been said I still had to change the battery after 3 years.

 

BMW was great for the key charging thing.
But yes, batteries dont last forever when with BMW charging.
Still need to be replaced.

Back to our benzes though, if battery is dead, can still pop keyless go button out, and insert key into ignition to start car i think.

As for getting in the car, with battery dead, yes, emergency key will manually unlock drivers door, and trunk.

 

+1 on both items.

 

It's keyless go. You don't insert the key anywhere - just keep in on your person or in your briefcase.