Fitting a new battery into the black key

[Davey P]

Can someone please tell me if the black remote key needs re-coding after fitting a new battery?  I've seen plenty of threads on here regarding the coding of a brand new key, but can't find any reference to a battery change on an existing key.  I assume the key still works with a flat battery inside, but would need inserting into the lock - And what sort of numpty would go to all that trouble, instead of simply pressing a button?  Ha ha!

I've got two black keys, plus one grey, so it's not urgent but I would like to sort it out anyway.

Cheers.

[Bossworld]

I'm 99% sure mine didn't need recoding but I hadn't let it go fully flat, I just noticed the range had reduced so swapped the battery out. Was probably batteryless for about 30 seconds tops.

[Davey P]

I'm 99% sure mine didn't need recoding but I hadn't let it go fully flat, I just noticed the range had reduced so swapped the battery out. Was probably batteryless for about 30 seconds tops.

Thanks mate, one of the keys was flat when I bought the car, so I don't know how long it's been like that.  I'll fit a new one and see what happens.

[StuC]

I have changed the batteries I my various keys and they all seem to work afterwards.