Key FOB Not Detected
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Joined: Aug 2013
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bmw530
Key FOB Not Detected
My 2014ML 550 is still having the issue where sometimes when I get into the car the push button start doesn't detect the key fob is in my pocket or in my hand. About 70% of the time it does work, but I can't find any common issue as to why it doesn't work the remaining 30%. So far, the dealer has replaced the battery and the then the entire key fob. Still hasn't solve the issue. Just wondering what's next as I have an appointment for my first Service A this Thursday. Thanks GaryNJ
Senior Member
Joined: Dec 2007
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From: Orange County, CA
'16 Jaguar F-Type R, '21 GLE63s
Do you have anything else on your keychain that might interfere with the RF signal? My sister had a similar problem and it turns out it was her work security badge that was causing the problem. Removing the badge from her keychain was the solution.
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Joined: Mar 2004
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From: Ft. Lauderdale Area, USA
2015 ML 350
Do you have a lot of coins or keys in the same pocket. Often when the keyless fails you can just "jingle" the pockets contents from the outside of the pocket & it will unblock.
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bmw530
Key Fob
I do have two other car keys (BMW's) but those key fobs require you to push a button either on the key itself or the other is just an alarm fob. I'll try to separate those two keys and just have the house key and MB key fob. No ID cards or magnetic strips are on my keys except for those two older BMW's keys.
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From: Ft. Lauderdale Area, USA
2015 ML 350
I keep the MB key with all my other keys in my Right pocket, and the Wife's BMW key in my Left pocket. (Both keys are Keyless Go type). I rarely have to jingle the MB pocket contents.
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Joined: Feb 2004
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'14 ML BT
The reliability of the fob and Keyless Go is not impressive. And the proximity unlock feature seems to work at about 75%.
I expect MB can do better than that. Shoot, I'd expect Chevy to do better.
I expect MB can do better than that. Shoot, I'd expect Chevy to do better.
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bmw530
I'm Thinking
Of always locking the car even when it sits in the garage. So that, when I go to use it I am forced to go through the unlocking process and maybe that will eliminating the key not detected once I push the button.
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Member
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ML350
I have the same issue with my 2014 ML350. Haven't reported it to the dealer yet. Been trying to figure out like the rest of you if something around me is interfering. Most of the time it works, but occasionally I get that not detected message
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bmw530
Back from Service with New Info on Key Fob (Software Update)
Had Service A done (oil change, windshield fluid added and cabin filters changed) and I still mentioned about key fob not detected even though they already replaced the battery and key fob from the two previous visits. Anyway, they discovered from MB center that there was a bulletin update called "LI80.61-P-060558" that updates the software to allow better communications between the car and key fob with regards to "key not detected". They uploaded the software and now I have to retest the functionality to see if the software update fixes the issue. GaryNJ
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Joined: Dec 2006
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From: Endicott NY
2014 ML350 Bluetec, 2016 GLC 300, 2023 Corvette, Z51 Stingray
I actually have this same issue with my 09 ML350. It only behaves this way when it is extremely cold outside. Battery in FOB is new. Headed in for service next week and will ask them if they have any ideas. Fortunately I have an independent MB shop and they usually can figure out the issue and or cause.
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From: Alberta, Canada
ml350 bluetec
I unlocked another ML350 in Finland with my fob, couldn't lock it too well, but it eventually worked. The guy who owned it was shocked. It's the only time it ever worked on a MB other than my own.
Member
Joined: Sep 2014
Posts: 204
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From: Calgary
GLE63S 2016
I have discovered the exact same behavior when my MB Fob is attached to the same key ring as any of my office/health club/home security fobs. I simply keep my fob all by itself now and I no longer have problems. I keep the fob zipped up in my jacket pocket and just basically forget about it. No problems since.
Super Member
Joined: Mar 2012
Posts: 619
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From: East part of Texas
2017 CLS550
Last night my dash display lit up in red and gave the same notice of not detecting the key. It did not indicate the battery was low. The display notice came on several times while driving and I also noticed I could not open or close the hatch with the remote all the time, only some of the time and was hit or miss. I will try my extra key today to see what happens.
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Joined: Dec 2014
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2020 E63S, 2019 GLE 43,2017 GLS450,2012 E350
This occasionaly happens on both my 2012 E350 and 2012 ML350 - Key not detected, usually with FOB sitting on passanger front seat. All I do is hit the unlock button on the FOB and the car starts right up. Never really thought too much of the issue but will mention at next services.
Last edited by jawman; Apr 9, 2015 at 07:23 AM.
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bmw530
Just an Update After the software Upgrade
Still was failing after software update if the vehicle sits for 4+ days in the garage as I only use it during the weekends. Dealer had it for two straight weeks and tried it three times during that period and of course it worked every time. After thinking about some more it seems to only show up when it sits in the garage. I do have an IP camera about 3 ft away from the vehicle on the outside of the garage. I'm going to unplug that camera and run my test starting next week.
Junior Member
Joined: Dec 2014
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From: Calgary AB
2012 ML350 BT, 1998 BMW 540i/6
Does it only fail at home... Or does it fail everywhere you drive? I'm wondering if something at home is interfering,like your wifi or a security motion sensor. If not other keys, then interference from your cordless home phone or other home based rf device perhaps?
Last edited by rtw_travel; Apr 9, 2015 at 09:42 AM.
Thread Starter
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bmw530
Home
It seems to only fail when it sits unused for a while (4+ days). On the weekends it gets used all day on both days and never fails to start in or out of the garage. But, that first start once after the long wait it will fail. I have to pull the button out to get it going. Once started, I can re-insert the button and it will continue to work. The only time it sits for a long time is in the garage. Lets see if the IP camera (which is only about 3 ft) away is causing the problem. If not then I'm going to have my wife started instead of me. The garage is a detached building about 30 ft from the main house. It also doesn't matter which key fob I use. The dealer has already replaced both batteries and one of the key fobs which didn't help.
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Joined: Dec 2014
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From: Calgary AB
2012 ML350 BT, 1998 BMW 540i/6
That's interesting.
I wonder if its an early warning that you car battery needs replacing. Or perhaps there is a poor solder joint on the connection from the battery/ fuse panel to whatever device detects the key fob. Either one of these would result in lower voltage at the key fob detector which may cause it not to work. But if you start the car and let the battery charge, the voltage would increase and it might work fine for a while.
On my BMW, when the battery starts to go, then the car throws some really weird electrical errors that seems to be completely unrelated to the car battery. Its funny because the battery is still strong enough to start the car, but the lower battery voltage causes things like the push button key fob not to work, or the idle speed to hunt from 500-800rpm, or other weird stuff. After 17 years of owning my 540, checking the battery has been my first thought every time anything electrical on my car fails - and it has been the culprit almost 100% of the time.
Hopefully this is on the right track to solve the problem. One simple test if you have a trickle charger: I wonder if the higher voltage of the trickle charger connected to the battery (after not running it for 4+days) would cause the fob detector to work. Try it without first, confirm is doesn't work, and then connect the charger and try again.
I wonder if its an early warning that you car battery needs replacing. Or perhaps there is a poor solder joint on the connection from the battery/ fuse panel to whatever device detects the key fob. Either one of these would result in lower voltage at the key fob detector which may cause it not to work. But if you start the car and let the battery charge, the voltage would increase and it might work fine for a while.
On my BMW, when the battery starts to go, then the car throws some really weird electrical errors that seems to be completely unrelated to the car battery. Its funny because the battery is still strong enough to start the car, but the lower battery voltage causes things like the push button key fob not to work, or the idle speed to hunt from 500-800rpm, or other weird stuff. After 17 years of owning my 540, checking the battery has been my first thought every time anything electrical on my car fails - and it has been the culprit almost 100% of the time.
Hopefully this is on the right track to solve the problem. One simple test if you have a trickle charger: I wonder if the higher voltage of the trickle charger connected to the battery (after not running it for 4+days) would cause the fob detector to work. Try it without first, confirm is doesn't work, and then connect the charger and try again.
Last edited by rtw_travel; Apr 9, 2015 at 11:02 AM.
Junior Member
Joined: Dec 2014
Posts: 60
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From: Calgary AB
2012 ML350 BT, 1998 BMW 540i/6
It sounds like it may not work... but the trickle charger is a simple and free test to do.
Bottom line - up to you. You can't know exactly what the dealer did: perhaps they stored it heated indoors and the battery maintained its charge better; or perhaps the dealer's car jockey had to move the car a few times, or decided to wash it, so it actually didn't sit.
Other than radio interference or car battery issues I can't think of anything else that fits the description.
Bottom line - up to you. You can't know exactly what the dealer did: perhaps they stored it heated indoors and the battery maintained its charge better; or perhaps the dealer's car jockey had to move the car a few times, or decided to wash it, so it actually didn't sit.
Other than radio interference or car battery issues I can't think of anything else that fits the description.
Junior Member
Joined: Dec 2014
Posts: 60
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From: Calgary AB
2012 ML350 BT, 1998 BMW 540i/6
Only one battery- in the engine compartment on the passenger side high up near the windshield. Have a look in your manual under 'battery' for jump start directions.
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2025 Panamera GTS
