Key battery
Thread Starter
Junior Member
Joined: Aug 2017
Posts: 56
Likes: 3
From: Toledo Ohio
2020 c300
Key battery
I'm going broke on batteries. I've tried every brand battery with both fobs and neither last more then a month, if that. It's a key fob. how many problems can there be?
MBWorld Fanatic!
Joined: Apr 2015
Posts: 1,739
Likes: 120
From: London ON Canada
2012 C300 4Matic Sport Sedan
There's something wrong then, I mean I just changed the batteries for the first time in 3 years just for precaution. Get a key fob case maybe your pushing and holding the buttons while it's in your pocket.
Member
Joined: Nov 2012
Posts: 178
Likes: 12
2013 C250
I don't even remember if I've ever changed mine, though I'm sure I have. More than once a year means you have a problem...probably with too much stuff in your pocket. Or its possible your battery terminals (where your battery touches the rest of the remote) are dirty and/or rusty. Spray some brake cleaner in there if its dirty and let it dry in a windy place.
Newbie
Joined: Feb 2019
Posts: 5
Likes: 0
2010 c350 4matic
Just to add to this, I just received Maxell batteries:
I changed the battery and still got the cluster warning.
Cracked open all batteries and read them with a multimeter : 3.29V, 3.09V. 3.09V, 3.09V, 3.26V
Turns out all 3.26V+ made the warning go away and all 3 others kept the warning (the one I swaped was 3.09V).
So I guess this is luck of the draw. You never know what voltage your new batteries will have.
I changed the battery and still got the cluster warning.
Cracked open all batteries and read them with a multimeter : 3.29V, 3.09V. 3.09V, 3.09V, 3.26V
Turns out all 3.26V+ made the warning go away and all 3 others kept the warning (the one I swaped was 3.09V).
So I guess this is luck of the draw. You never know what voltage your new batteries will have.
