Key problems on '00 BMW 7 Series - rhino
My father in law has just been charged over a hundred pounds for a new key for his BMW. The problem was the gradual inability of the key to lock/unlock the car remotely, which to me pointed to a new battery.

The dealer simply ordered him a new key.

I managed to get the old one apart just before he left today, but the battery didn't want to come out easily before he had to go.

Are battery changes possible with these? I get the feeling the dealer went for the easy option.
Key problems on '00 BMW 7 Series - trancer
My'02 BMW key has non-replaceable batteries so its a new key when it stops holding a charge. Don't know when they were introduced, but its possible your father in laws is the same.
Key problems on '00 BMW 7 Series - rhino
Thanks; given the proximity of models I wouldn't be surprised.

What a bizarre setup! Yet another example of manufacturers gently easing DIY out of the menu of options to ensure they benefit from pricey aftermarket business.
Key problems on '00 BMW 7 Series - Aprilia
IIRC the battery on these is actually rechargeable and is kept 'topped up' by an inductive charging loop around the lock barrel. I don't think changing the battery is possible - so it has to be a new key. I heard it said (by a trader, not BMW) that they last about 4-5 years before the battery 'wears out'. I think they cost about £150 ??
Key problems on '00 BMW 7 Series - Bill Payer
I heard it
said (by a trader, not BMW) that they last about 4-5
years before the battery 'wears out'.

So I guess for BMW's target market (company owned new cars) then that's fine, as they'd typically be ditching the car after 3 yrs.
Not very environmentally friendly of BMW, though.
Key problems on '00 BMW 7 Series - trancer
The BMW ones go for about £100 from a main dealer. I haven't had to buy one yet, but others on a BMW forum I frequent have.

Another tidbit I heard (may just be rumour) is that BMW make 10 keys for each car and these keys are then ordered by main dealers as and when needed. The local dealer doesn't actually cut the key, it comes from the factory already cut and coded to your car. Apparently if you should happen to lose lots of keys and get through all 10 it will mean new lock barrels and a immobilizer ECU.

This sounds far fetched to me as I can't imagine BMW storing millions of keys for all the cars it sells. It is much more likely that the coding and cutting information is stored and then new keys cut to order by the Factory etc.
 

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