How long will the key battery last after "replace key battery" warning
#2
MBWorld Fanatic!
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No, that’s why I have a spare battery sitting on the little shelf in the front part of the center console
#3
Super Member
#4
Member
Keyless go drains battery faster. If you want to save battery of a spare key, double click the lock button of the spare key. It will turn off keyless go function of the key. To turn it on again, simply click the unlock button. I replace the battery once a year. $1/year. If not keyless go, I could use it for 5+ years.
![Lockd](https://mbworld.org/forums/images/smilies/lockd.gif)