pamiboy

My car is showing a message "Change Key battery" today. I have a four year maintenance plan with MB. Will this be covered under warranty or is this considered an expendable / wear & tear item? Thanks.

beshannon

Well since it is a $2.50 battery and takes 30 seconds to change you should probably just do it.

pamiboy

Thanks for that information. But what are the specs of the battery and where can I get it from?

hyperion667

it's a 2025 battery chip and can be found practically anywhere......just got the message in my cls last night.....I highly doubt it's under warranty LOL...


the directions are even in the manual
I always get the two pack and leave one in each car

beshannon

http://www.mbusa.com/mercedes/owners...007d184335RCRD

philesk

Just bought CPO E350 last night. After driving home from dealer, got the "Replace Key Battery" warning and an image of the smart key. Dealer will give me new battery.

BUT..

This car also has Keyless Go. Does the start/stop button also have a battery?

pcsgrp

I just changed two of them on my wife's Key and this morning I got the notice on one of my keys. I guess they transmit all the time with keyless just like a cell phone. It sure looks like you get 1 year out of a battery even if you never use it.


This car also has Keyless Go. Does the start/stop button also have a battery? That is just a little plastic button

hyperion667

the car talks to the key when it's in range, but probably not while you're in your house or office, and I'm pretty sure there is no battery in the S/S button

mikemargolis

because Walgreens gets like $5 each, and on ebay I can get them for $1 each, no shipping.

I may have an expensive car, but I am cheap!

pamiboy

I bought the batteries and replaced them in the key today. Thanks guys.

mikeyle

my battery is still good after 17 months of everyday use, bought off of amazon, sony

philesk

Thanks for posting the video link. I looked at a couple of CR batts I had sitting around the house, found one was a SONY CR 2025, followed the video noting that my remote did NOT make the little red light flash before changing the battery.

With the new battery, lock & unlocks car, red light flashes and all is ok. The warning has cleared and keyless works.

We shouldn't have to go to the dealer for EVERY little thing....

hyperion667

mikemargolis

Huh, 65000 miles on my car, and I never knew about the red light on the key.

Have sometimes wondered if it was my key or my wife's that was causing the warning.

You learn something new every day!

thenew3

In my experience, the battery in the key will last a good 3 to 4 years if you don't have keyless go. With the keyless go package, the batteries seem to last only about 6 to 10 months.

I usually just by a 5pk off ebay for $1 to $2. I tested with name brand (sony/panasonic) vs cheap generic chinese knock off from ebay, they all get about the same life span of around 6 to 10 months. So just buy a 5pk for $1 on ebay vs $5 for a single name brand battery.

BenzV12

I have inspected these batteries and funny thing may be coincidence all of these type of 2025s are made in Indonesia .
I have Panasonic but ended up buying GP .I have already replaced two batteries in both key fobs .Keyless Go consumes up battery life lol
Well, there is another exact size but thicker 3V battery . I forgot what it's name was say 3225 . I could buy it instead on purpose for lasting longer as opposed to 2025's but I didn't buy it because I thought it would not fit because if it's thickness .
I think manual should cover about compatible sizes or types about it

pcsgrp

I changed mine the other day but used a different FOB to unlock the car. When I sat in the car with the FOB I just installed a new battery, the car did not see the key and came up with that message that no key found. I had to unlock the door using the FOB and then it would start. When I got to the football game, I locked the car using the lock button on the tailgate and after we came out, keyless open using the inside of the handle would not unlock the doors. Had to use the button on the FOB. It wasn't until I got home and used the car again did everything seem to work. I wonder if there is some sort of "syncing" needed if you use two different FOBs to unlock the doors

RSIKR

Something worth remembering. You may know this as it is covered in the manual.

!. If you were stuck with a non functioning key fob, Keyless Go or non you can extract the metal key from the electronic fob to unlock the driver's door.

2. If your car has the Start/Stop button remove it by pulling straight out and insert the key fob like a non keyless go car. The vehicle will read the chip in the key when inserted.

pcsgrp

Yep, remember that from my wife's car. I also found that cycling the FOB by unlocking and locking doors also works

RSIKR

You are right, I recall my car going into super deep sleep after not being used for several days and the elves who man the touch the door handle and kick under the bumper to open were off duty. Cycling the fob woke everything up. No battery deficiencies on the fob or the car, just a deep sleep or bad hangover on their part. The deep sleep is probably battery conservation for the car. The Keyless Go fob and car transceiver system is a lot like the cell phone analogy others have put forth. The love bugs are just trying to mate.

hyperion667

keyless go/entry is worth it IMO, I never want a car without them again LOL
I'll buy however many batteries it takes!


wonder how much a dealer would charge to do it haha!

RSIKR

I agree Keyless Go, handsfree access and electronic (foot kick) closer is well worth it.

Here is a link to real MB CR2025 batteries. On Amazon for "only" $7.57 a pair. As I recall I have seen them offered at list price which I believe is $9.99 a pair.


They are as real as the ones that sell for $2-4 a pair & worth having extras at that price. The shelf life is about ten years.

Another thought about the "mating" habits of car and fob. If you are walking around an area with other MBs key and fob are exchanging signals looking for their mate, eating up electrons. Likewise if you are in range near your car with the key for long periods.

pcsgrp

I agree, keyless is great. I didn't think I wanted it on the wife's E350 last year but I grew to really like it. When I got my ML, it had it so I was fine with it. Don't care about spending a few $s/year for batteries the convenience it provides is great. As for batteries, I ordered 5 on amazon and they cost $3.50 free shipping. I found that a few other thingsI have at home use the same 2025 battery including camaras and remote controls

Johnny Rad

Keyless Go might be the single most important feature on my future cars.

If your other car doesn't have it, how irritating is it to dig the key out of your pocket to start it?! For such a small and seemingly trivial feature before you have it, it's a game changer once you do.

pcsgrp

[QUOTE=Johnny Rad;6213000]Keyless Go might be the single most important feature on my future cars.

Agree, the only down side I see is that they figured out how to scan the frequencies and hack the keyless. I think it varies on how easy between brands but I recall reading that it is a problem with people getting inside cars and stealing everything. I don't think they can drive away with them yet