Remote Controller on Key
 

One of my key remote controller no longer works. I suspect the battery is dead. Any idea how I can get a replacement battery or what I should do.

The battery is recharged by inserting the key in the ignition and using it. Try this and see if it brings it back to life.

The handbook says to rotate the keys every six months to keep the batteries charged.
colin.

My battery died recently and got replaced by the Dealer. Now, my wife's key doesn't remotely lock/unlock the doors anymore, nor does it seem to remember her favorite positions. The manual said it needs to be charged every 6 months or so and she is the main driver of the car so I'm suspecting the key is not getting charged. What should I do? Would this be covered under warranty? Thanks.

If your X is under warranty, it should be covered.

A rechargeable battery can only be recharged a certain amount of times. Once its at the end of its life it will no longer hold a charge. You have really 3 options.

1) Buy new key from bmw dealer
2) Replace key in old remote (Requires cutting open the old key and special ordering the recharageable battery online only from an electronics website)
3) Find a blank key on ebay (Will be hard to find someone to cut it and program it, not really worth it, just buy one from the dealer works out to be the same price)

the KEY is not and cannot be programmed. the car's computer is programmed to accept the key as a valid one.

UncleBob - I agree with you here.
Where people get confused is that any key off ebay or similar sources can easily be programmed to open the doors, etc. but it cannot be programmed to start the engine. Aside that the physical cutting of the key will be wrong

Been there, done that

I'm also suprised that an earlier post refer to the dealer changing the battery. I find this hard to believe unless they have nade some changes to the key as I know from experience the key casing cannot be opened short of sawing it up and rebonding and secondly the battery is spot welded to its contact points.