Vrodman

Anybody finding they need to replace their key battery every 2 to 3 months?

For the last year this has been the pattern.

Is this a cost of going push-button start? I don't think these batteries get charged by the car though do they?

Anyway, just wondering.

Cheers

PeterUbers

Sup man!

About every 6 months here ... Ironically just got the key battery low warning yesterday AGAIN

The batteries are like $0.40 each on Amazon cr2025

Vrodman

Yeah, I have a pack of them. Just seems like a pain in the **** every three months.

I replaced my first battery in my old e55 key after 14 YEARS!

That car wasnt push start though. Thats why I asked about that.

Anyway, Cheers Bud. Hope you have a great holiday weekend.

6G Schnell

I have push button start and replaced key battery after 18 months, or more. Starting the car twice a day, on average.

Three months seems excessive; if you are not unlocking the doors/starting the car dozen times a day, maybe worth checking if batteries are fresh and full capacity?

Gene Gorman

What is the battery number? I would like to buy some so I will have them on hand when I need one.

6G Schnell

CR 2025 available at Amazon, like Peter suggested.
I would only add one detail: store them in the fridge so they keep capacity.

screw991le

6-8 months here with the keyless go. I ordered a few dozen Duracell from eBay for around $25 with freshness date until 2025.

CliffJumper

Wow, I didn't realize these Mercedes keys were so bad. I only replaced my pushbutton M3's key once in over five years and my S4 key still has a very long range after one year.

PeterUbers

Good call on refrigeration I just moved my box of batteries to our fridge my wife thinks I'm delirious ...

Johnny Rad

I vaguely recall reading the battery life may be longer if it's stored far enough away from the car. The posted recommended not leaving the key in the car when it's parked or on a key hook in the garage. Something about getting it out of range.

Johnny Rad

That's a good tip. Even if they're an off-brand and/or don't last quite as long, I've been happily making this trade-off for awhile now.

By the way, how do these vendors make money on these?! I just bought two 5 packs and paid something like $5-6/shipped from the Far East.

PeterUbers

Oh interesting... My bag has my key fob and it's like always about 30 ft from the Benz separated by an insulated wall

CliffJumper

Hmm, my S4 key is always on a key hook about 3 feet from my car. Not even close to dying after a year. Odd the MB one dies so fast. I guess I'll find out soon.

JJCTHE1

They typically should last longer than 3 months. It's possible you have the keys too close to the car when not in use. The new Benz keys only take 1 battery the old ones took 2 and I remember they lasted years.

2012 merc amg

Yes, don't leave key too close to car. I get a year out of batteries on my 2012 with push button start. Something does not sound right to have the battery go every 3 months.

benyl

I started using 2032s as they have more capacity. Slightly thicker but last much longer.

EddieK

Won't fit in my 2014 key fob.

LJMartin

My first battery lasted about a year, the second about the same. I then went through a spell where they were lasting about 6 weeks. Now it's back to normal. It didn't matter what brand I used.

TonyC

lols. even the key fob battery gets "modified!"

will try after my 4 pack of 2025s run out... (i've already used 2 in a year)

screw991le

hummm 2032s here I come.

Johnny Rad

This is a "you get what you pay for update" news flash on cheap key fob batteries. I bought a couple packs for next to nothing awhile back. In the past couple of months, I've had to replace them twice and in dong so ran into some already dead batts in the packs that wouldn't light the red blinky on the fob. You win some, you lose some!

This time around, I read the reviews and found a couple of sellers that were selling major name brand batts that probably weren't out of date / expired batts. I'm off to a good start with them, so we'll see. They're still cheaper and more convenient than the local supermarket.

Traffic53

just echoing the proximity of the key fob to the car when you're not using it. when the key fob is within 15ft or so of the car, it draws power, however slight. so, if you leave your keys in the car in the garage- like i used to do- you'll replace battery every 6-8 weeks.

cadeca

That's odd. I keep my keys inside, but only about 8 feet from my car. Batteries have lasted over a year. Could the insulated wall make that big a difference?

Astolfo

the fridge or oven, by lowering the temperature you force to lower the voltage when warming back up that consumes capacity and the battery never recovers it voltage under load.


Would you put your car battery in the fridge and expect it keep its voltage and capacity? I bet not....
the inverse is true for heat.
At the end you lose capacity and linear voltage.


Dry place constant ambient room temperature is the best way to store any battery.

E55 KEV

LOL! I had to change battery and the key was kept in another house.

I've change battery in both keys and my car has 1050 miles on it. Yes 1050.