Key Battery change
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MBWorld Fanatic!
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E 350
Key Battery change
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.
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From: on my way
2012 CLS63
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
the directions are even in the manual
I always get the two pack and leave one in each car
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2014 E350 Sport
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Joined: Nov 2013
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From: San Francisco bay Area
2013 E350 Sedan (P2) Parktronic, Lane Assist; 2009 E350 Sedan (totalled)
Great video
BUT..
This car also has Keyless Go. Does the start/stop button also have a battery?
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E350 4-Matic, GLE350, Harley Davidson Electra Glide
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
This car also has Keyless Go. Does the start/stop button also have a battery? That is just a little plastic button
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Junior Member
Joined: Nov 2013
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From: San Francisco bay Area
2013 E350 Sedan (P2) Parktronic, Lane Assist; 2009 E350 Sedan (totalled)
Changed Battery myself - All is OK
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....
Last edited by philesk; Oct 27, 2014 at 08:25 PM. Reason: more info
MBWorld God!
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From: on my way
2012 CLS63
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. I will check to see if the warning clears and keyless works next time I start the car.
We shouldn't have to go to the dealer for EVERY little thing....
With the new battery, lock & unlocks car, red light flashes and all is ok. I will check to see if the warning clears and keyless works next time I start the car.
We shouldn't have to go to the dealer for EVERY little thing....
Super Member
Joined: Feb 2011
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'11 E350BTC P2 Leather
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!
Have sometimes wondered if it was my key or my wife's that was causing the warning.
You learn something new every day!
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From: Central Coast, CA
2020 X7 xDrive40i, 2016 X3 sDrive28i
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.
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.
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W212 FL
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
.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
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E350 4-Matic, GLE350, Harley Davidson Electra Glide
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
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2014 W212 E350 4M
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.
!. 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.
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2014 W212 E350 4M
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.
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2014 W212 E350 4M
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.
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.
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E350 4-Matic, GLE350, Harley Davidson Electra Glide
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
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From: Zion
W212 E550 4M P2
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.
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.
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Joined: Dec 2012
Posts: 160
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E350 4-Matic, GLE350, Harley Davidson Electra Glide
[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
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
