PSA - first sign your keyfob battery needs changing
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From: Las Vegas
2012 E350 sedan
PSA - first sign your keyfob battery needs changing
I noticed the fob would not lock the car. The unlock and trunk feature worked and the fob LED flashed on both of those buttons but not the lock button.
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Senior Member
Joined: Aug 2014
Posts: 255
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From: Las Vegas
2012 E350 sedan
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From: V E G A S
1922 Ford Model T / no OBD
My battery is on its 2nd year as well and still good.
I don't press any button on the remote.
Once I put remote in my pocket in the kitchen, it stays in my pocket till I am back in my kitchen after the trip.
I use door handles sensors for locking/unlocking or trunk bottom sensor for opening with foot.
I don't press any button on the remote.
Once I put remote in my pocket in the kitchen, it stays in my pocket till I am back in my kitchen after the trip.
I use door handles sensors for locking/unlocking or trunk bottom sensor for opening with foot.
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From: Pepper Pike Ohio
24 GLS580 '23 E450 4matic 12 E350 4Matic
I have a 12 without keyless go and a 13 with keyless go, the 13 needs a new battery every 9 months or so and tells you so with a dash light, my 12 will go three years on a battery {larger battery 2025 vs 2032} and will not get a dash code until you already know the battery is dead because it stops working, first range goes then lock goes, then unlock, all before I get a dash light.
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2013 E550 sedan
Our '13 with keyless go eats FOB batteries as well. I've tried moving them farther from the car, wrapping in foil, nothing seems to help - I don't think any have lasted even near a year. CR2025s is what ours take, reminds me I better order more... Ours tells us via the dash also.
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From: V E G A S
1922 Ford Model T / no OBD
Per my observation and forum exchange, the key sends a ping every 3 or 5 seconds no matter what, so wrapping, or shielding is not going to change it.
But as I mention above, I don't press the buttons on the remote and I don't carry it in pocket with other junk, so the buttons don't get pressed while on the road.
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From: Pepper Pike Ohio
24 GLS580 '23 E450 4matic 12 E350 4Matic
Well, for the last 25 years I've left my Mercedes keys in the top of my toolbox in the garage, this was fine for my 93 and 03 S500's, also for my 12 without keyless go, I take my 13 key in the hose now because if I leave it in the garage the battery goes dead in three months if I leave the key within 20 feet of the car. As you may have guessed, I use the remote to unlocki and lock, also to open and close the trunk on the 13 mostly because I forget to use the door lock and unlock feature on the door handles. After reading your post, I am trying to use those features to see if the battery lasts longer that way. Also as I mentioned the 12 uses a 2032 battery as did my S classes and the 13 keyless go uses a 2025 battery which is smaller in thickness by 1/3.
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Joined: Aug 2014
Posts: 255
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From: Las Vegas
2012 E350 sedan
Thanks
I have a 12 without keyless go and a 13 with keyless go, the 13 needs a new battery every 9 months or so and tells you so with a dash light, my 12 will go three years on a battery {larger battery 2025 vs 2032} and will not get a dash code until you already know the battery is dead because it stops working, first range goes then lock goes, then unlock, all before I get a dash light.
My wife was stranded during a vacation when the key would not work at all. She went into a restaurant, came out, and the car would not turn over. Had to tow the car 50 miles to the nearest dealer (fortunately under CPO warranty). It took them almost a week to fix it because they had to order a replacement key from Germany. We now keep the spare key in the trunk.
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2013 E550 sedan
Well, for the last 25 years I've left my Mercedes keys in the top of my toolbox in the garage, this was fine for my 93 and 03 S500's, also for my 12 without keyless go, I take my 13 key in the hose now because if I leave it in the garage the battery goes dead in three months if I leave the key within 20 feet of the car. As you may have guessed, I use the remote to unlocki and lock, also to open and close the trunk on the 13 mostly because I forget to use the door lock and unlock feature on the door handles. After reading your post, I am trying to use those features to see if the battery lasts longer that way. Also as I mentioned the 12 uses a 2032 battery as did my S classes and the 13 keyless go uses a 2025 battery which is smaller in thickness by 1/3.
And on the key going dead and having to get a new one, that is odd - ours you can open the door with the valet key in the fob, remove the start/stop button and insert the key fob in there and it functions like a normal key...
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From: V E G A S
1922 Ford Model T / no OBD
Agree that key will operate the car without battery as ignition chip is passive one and mechanical blade for the door is.. mechanical.
Now about the range, I did some testing and it is not more than 6 feet for me.
I show off the feature when I leave the car with doors locked, step back 6 ft and ask friend to open the car. He can not, so I make 5 steps and open it without the trouble. Than I lock the car, step back 6 ft and he can't open it again.
That said, few times I had key in my pocket and stood 3' behind my wife trying to open passenger door and sometimes it would not work. I had to touch the lock. So the 3' seems to a border, when I don't know if driver and passenger door sensors have the same sensitivity.
My cars go to sleep, meaning all the displays go off in about 10 seconds and I had car sitting in garage for 3 weeks and battery hold the charge.
Just beware that sometimes Bluetooth connection keeps the car awaken.
Now about the range, I did some testing and it is not more than 6 feet for me.
I show off the feature when I leave the car with doors locked, step back 6 ft and ask friend to open the car. He can not, so I make 5 steps and open it without the trouble. Than I lock the car, step back 6 ft and he can't open it again.
That said, few times I had key in my pocket and stood 3' behind my wife trying to open passenger door and sometimes it would not work. I had to touch the lock. So the 3' seems to a border, when I don't know if driver and passenger door sensors have the same sensitivity.
My cars go to sleep, meaning all the displays go off in about 10 seconds and I had car sitting in garage for 3 weeks and battery hold the charge.
Just beware that sometimes Bluetooth connection keeps the car awaken.
Last edited by kajtek1; Jan 29, 2020 at 02:51 PM.
Member
Joined: Jul 2019
Posts: 169
Likes: 76
2013 E550 sedan
Agree that key will operate the car without battery as ignition chip is passive one and mechanical blade for the door is.. mechanical.
Now about the range, I did some testing and it is not more than 6 feet for me.
I show off the feature when I leave the car with doors locked, step back 6 ft and ask friend to open the car. He can not, so I make 5 steps and open it without the trouble. Than I lock the car, step back 6 ft and he can't open it again.
That said, few times I had key in my pocket and stood 3' behind my wife trying to open passenger door and sometimes it would not work. I had to touch the lock. So the 3' seems to a border, when I don't know if driver and passenger door sensors have the same sensitivity.
My cars go to sleep, meaning all the displays go off in about 10 seconds and I had car sitting in garage for 3 weeks and battery hold the charge.
Just beware that sometimes Bluetooth connection keeps the car awaken.
Now about the range, I did some testing and it is not more than 6 feet for me.
I show off the feature when I leave the car with doors locked, step back 6 ft and ask friend to open the car. He can not, so I make 5 steps and open it without the trouble. Than I lock the car, step back 6 ft and he can't open it again.
That said, few times I had key in my pocket and stood 3' behind my wife trying to open passenger door and sometimes it would not work. I had to touch the lock. So the 3' seems to a border, when I don't know if driver and passenger door sensors have the same sensitivity.
My cars go to sleep, meaning all the displays go off in about 10 seconds and I had car sitting in garage for 3 weeks and battery hold the charge.
Just beware that sometimes Bluetooth connection keeps the car awaken.
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From: Dallas-Ft.Worth,TX
2016 E350 Sport
Our '13 with keyless go eats FOB batteries as well. I've tried moving them farther from the car, wrapping in foil, nothing seems to help - I don't think any have lasted even near a year. CR2025s is what ours take, reminds me I better order more... Ours tells us via the dash also.
Last edited by DFWdude; Jan 29, 2020 at 09:11 PM.
Member
Joined: Jul 2019
Posts: 169
Likes: 76
2013 E550 sedan
Correct, wrapping in foil will not work... Foil just acts like an external antenna. You might want to read this related thread. It's mostly about fob security, but also addresses some facets of battery drain... https://mbworld.org/forums/e-class-w...-security.html
, but was hoping the deactivate would work for me...
