Just figured out why my key fob battery keeps dying

M4Now! · 10-22-2011, 10:23 AM

The battery in my fob was lasting about a month, which was pretty annoying. Today though, I walked out to the car, and just as I touched the door handle thought "crap, don't have my keys." And the door unlocked.

Apparently the range of Convenient Access is greater than the manual says, and the desk where we keep our keys is about ten yards from the car in the garage. Since the fob responds to the car signal by transmitting, ten yards must be close enough for them to constantly communicate, and thus drain the battery. Problem solved!

Cheers

1sikbmr · 10-22-2011, 10:41 AM

sounds reasonable but I thought that would drain the car battery as well.

radiantm3 · 10-22-2011, 11:24 AM

Don't think that is the case. If it is, doesn't sound normal. My keys are 10-15 feet from my car and have been that way for almost a year now. I have yet to replace my battery.

Mike van D · 10-22-2011, 11:59 AM

Same here, keys within 15 feet and zero problems like that.

SchnellM3 · 10-22-2011, 12:19 PM

No problems here either

M4Now! · 10-22-2011, 12:21 PM

Hmmm, maybe you're right, I couldn't reproduce it a few minutes ago. Drat.

abehwang · 10-22-2011, 12:28 PM

my car talks

thai357sig · 10-22-2011, 02:09 PM

Not so with my car. When I wasH my M, and the FOB is in my pocket, the doors would constantly lock and unlock. So I put the FOB eight feet away sitting on me stereo. No more unwanted locking. Also when done and the doors are locked, I could not unlock it with the eight foot distance.

GIdriver · 10-22-2011, 02:23 PM

Quote:

Originally Posted by M3Now!

The battery in my fob was lasting about a month, which was pretty annoying. Today though, I walked out to the car, and just as I touched the door handle thought "crap, don't have my keys." And the door unlocked.

Apparently the range of Convenient Access is greater than the manual says, and the desk where we keep our keys is about ten yards from the car in the garage. Since the fob responds to the car signal by transmitting, ten yards must be close enough for them to constantly communicate, and thus drain the battery. Problem solved!

Cheers

Not normal. The car should not lock/unlock unless the key is really colse to the car.

GIdriver · 10-22-2011, 02:25 PM

Quote:

Originally Posted by GIdriver

Not normal. The car should not lock/unlock unless the key is really colse to the car.

^correction: ...close to the car

08E92M3 · 10-22-2011, 07:18 PM

Quote:

Originally Posted by thai357sig

Not so with my car. When I wasH my M, and the FOB is in my pocket, the doors would constantly lock and unlock. So I put the FOB eight feet away sitting on me stereo. No more unwanted locking. Also when done and the doors are locked, I could not unlock it with the eight foot distance.

That happened to me a couple of times when I was washing my M, I ended up taking my key out of my pocket & put it somewhere inside the garage. The battery in the key lasted a few months short of 3 years, so, that wasn't too bad!

JCtx · 10-22-2011, 07:52 PM

Quote:

Originally Posted by M3Now!

Apparently the range of Convenient Access is greater than the manual says, and the desk where we keep our keys is about ten yards from the car in the garage.

Really? I have to drag myself against the door to get the freaking CA to unlock the door

. And that's with a NEW battery. And same for starting the car with key in my pocket. Have to try several times until it senses it. POS system IMO. Funny thing is we have a Hyundai and it's been flawless for a year. Hmmmm.

Erie Von Otto · 10-23-2011, 01:37 AM

^^^This.

Acts how it wants to. Sometimes, and its always when someone is looking, I'm standing there pulling the door handle to open and it wont unlock. Or pressing the trunk button and it wont open. PIA. But whenever I'm washing it, boy that sucker wants to lock/unlock all day long. Nevermind that once I get in the car, I sit there pressing the button until I finally have to take the key out and insert it to get the car to start.

I talked to BMW master tech and he said to plug it in every once in a while because it recharges the secondary battery in the FOB. I said ok, tried it(with both keys mind you), and it made 0 difference.

I'm at about 75% "working as advertised" right now.

mkoesel · 10-23-2011, 05:59 AM

Quote:

Originally Posted by ottoblotto

I talked to BMW master tech and he said to plug it in every once in a while because it recharges the secondary battery in the FOB.

This master tech really ought to read the manual...

Stronghammer · 10-23-2011, 06:15 AM

I think the owners on the only one's that read the manual. Heck my service advisor didn't even have a manual.

M4Now! · 10-23-2011, 11:51 AM

Quote:

Originally Posted by ottoblotto

^^^This.

Acts how it wants to. Sometimes, and its always when someone is looking, I'm standing there pulling the door handle to open and it wont unlock. Or pressing the trunk button and it wont open.

Ha! This happens to me all the time

Hix · 10-23-2011, 05:07 PM

Thing about BMW comfort access is that it works some of the time maybe... Pretty much as long as I am in no hurry and nobody is around. The girl I was dating has a Murano with a similar setup and it always works the first time as soon as she the touches the thumb thing. Really annoying.

Boostin FD · 10-24-2011, 09:14 AM

Same thing happens to me often... the other thing that bothers me is that the key fob won't unlock the car if you press the button, unless you are as close as 6ft. In my Audi, i could unlock the car from inside my apartment which is about 50 ft away.
Yet with BMW, you have to be very close... I replaced the darn battery just past weekend.

///My5UV · 10-24-2011, 09:58 AM

Maybe some of you folks are in an area with alot of radio interference?
I have noticed that the CA barely works if I have the key in the same pocket as my phone.

Nelrock · 10-24-2011, 12:02 PM

Quote:

Originally Posted by elp_jc

Really? I have to drag myself against the door to get the freaking CA to unlock the door

. And that's with a NEW battery. And same for starting the car with key in my pocket. Have to try several times until it senses it. POS system IMO. Funny thing is we have a Hyundai and it's been flawless for a year. Hmmmm.

I hear that!
I closed the trunk lid on my fob once. It's in the car...the trunk would just reopen right? Uh...no. I had to go hit the trunk release.

Erie Von Otto · 10-24-2011, 12:51 PM

Quote:

Originally Posted by ///My5UV

Maybe some of you folks are in an area with alot of radio interference?
I have noticed that the CA barely works if I have the key in the same pocket as my phone.

Nope. I took the key out of my pocket, held it in the hand basically laying it on top of the door handle, and still didnt work. This has been from the get go with the car. The first time I brought it up to the tech was three weeks after picking the car up. He swapped out the battery and all was good for a few days. Then it just randomly does what it does...

Mike van D · 10-24-2011, 02:16 PM

Know a couple of folks who had the CA not work right and had the door handle cover replaced...said it's fixed the problem so far.

10-22-2011, 10:23 AM	#1
M4Now! Captain 292 Rep 708 Posts Drives: MG / SO F83 Join Date: Sep 2011 Location: Texas iTrader: (0)	Just figured out why my key fob battery keeps dying The battery in my fob was lasting about a month, which was pretty annoying. Today though, I walked out to the car, and just as I touched the door handle thought "crap, don't have my keys." And the door unlocked. Apparently the range of Convenient Access is greater than the manual says, and the desk where we keep our keys is about ten yards from the car in the garage. Since the fob responds to the car signal by transmitting, ten yards must be close enough for them to constantly communicate, and thus drain the battery. Problem solved! Cheers __________________ Bye bye E93 M3 - Hello F83 M4!
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10-22-2011, 10:41 AM	#2
1sikbmr Brigadier General 145 Rep 3,329 Posts Drives: F80 M3 6MT Join Date: Mar 2010 Location: New York iTrader: (16)	sounds reasonable but I thought that would drain the car battery as well. __________________ F80 ///M3 6MT Avus Blue ZCP
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10-22-2011, 11:24 AM	#3
radiantm3 Apex Everything! 976 Rep 4,378 Posts Drives: 2007 Honda S2000, 2017 GT350 Join Date: Sep 2008 Location: Cedar Park, TX iTrader: (6) Garage List 2011 E92 M3 [9.35] 2014 BMW i3 [10.00]	Don't think that is the case. If it is, doesn't sound normal. My keys are 10-15 feet from my car and have been that way for almost a year now. I have yet to replace my battery. __________________ 2011 E92 M3(Sold). 2007 Honda S2000 (Track Car). 2016 Cayman GT4 (Sold). 2017 Shelby GT350 (AKA Crowd Killer). My pet project: https://stickershift.com
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10-22-2011, 11:59 AM	#4
Mike van D Major 18 Rep 1,112 Posts Drives: SG X6 35i; MW e92 M3 Join Date: Jan 2011 Location: Germany iTrader: (0)	Same here, keys within 15 feet and zero problems like that. __________________ ...just enjoying life.
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10-22-2011, 12:19 PM	#5
SchnellM3 Digger 205 Rep 2,619 Posts Drives: 03 E46 M3 Join Date: Jun 2009 Location: Pa iTrader: (5) Garage List 2003 BMW E46 M3 Tra ... [8.00] 2009 BMW E92 M3 [8.30] 2009 Yamaha R1 (FOR ... [9.50]	No problems here either __________________ 2009 E92 M3 /// Melbourne Red /// Fox Red /// M DKG Full Innotech Exhaust - DINAN Intake - IND Engine Bay Appearance - IND Hand Stitched Boot Covers - and much more....
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10-22-2011, 12:21 PM	#6
M4Now! Captain 292 Rep 708 Posts Drives: MG / SO F83 Join Date: Sep 2011 Location: Texas iTrader: (0)	Hmmm, maybe you're right, I couldn't reproduce it a few minutes ago. Drat. __________________ Bye bye E93 M3 - Hello F83 M4!
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10-22-2011, 12:28 PM	#7
abehwang Captain 36 Rep 547 Posts Drives: e90 m3 Join Date: Mar 2011 Location: US iTrader: (0)	my car talks __________________ 2008 E90 M3: Alpine White/ Fox Red Novillo/ Brushed Aluminum \| 6MT \| Premium \| Cold Weather \| Technology \| EPS \| PDC \| Ipod/USB \| Fuelly :: Adelei's Gas Mileage
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10-22-2011, 02:09 PM	#8
thai357sig Lieutenant 30 Rep 409 Posts Drives: M3 Join Date: Jan 2009 Location: Amerika iTrader: (0)	Not so with my car. When I wasH my M, and the FOB is in my pocket, the doors would constantly lock and unlock. So I put the FOB eight feet away sitting on me stereo. No more unwanted locking. Also when done and the doors are locked, I could not unlock it with the eight foot distance. __________________ 09'M3 JerezB/Tech/Cold/Prem/PDC/SR/Black Leather/ANTHRACITE Sycamore/IPOD/USB/Rear Sunshade/Premium Sounnd/6MT*Just Hit The Ground! Delivery 02/25/2009*
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10-23-2011, 01:37 AM	#13
Erie Von Otto DT///M 149 Rep 1,370 Posts Drives: 2014 F31 Touring Join Date: Apr 2011 Location: Rocket City, AL iTrader: (3) Garage List 2014 BMW Touring [0.00]	^^^This. Acts how it wants to. Sometimes, and its always when someone is looking, I'm standing there pulling the door handle to open and it wont unlock. Or pressing the trunk button and it wont open. PIA. But whenever I'm washing it, boy that sucker wants to lock/unlock all day long. Nevermind that once I get in the car, I sit there pressing the button until I finally have to take the key out and insert it to get the car to start. I talked to BMW master tech and he said to plug it in every once in a while because it recharges the secondary battery in the FOB. I said ok, tried it(with both keys mind you), and it made 0 difference. I'm at about 75% "working as advertised" right now. __________________ "With great power comes great responsibility." -El-Superbeasto
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10-23-2011, 06:15 AM	#15
Stronghammer Lieutenant 42 Rep 590 Posts Drives: E92 M3 Join Date: May 2011 Location: south carolina iTrader: (3)	I think the owners on the only one's that read the manual. Heck my service advisor didn't even have a manual. __________________ 2011 E92 M3 MR July 11 ED Sept 11 PCD Mods: ESS VT1, MS test pipes, 19 BBS CH-R, Eibach pro springs, Painted reflectors, carbon fiber grills, Painted side markers with dark tinted lenses, 30% tint, Arkym rear diffuser, Innotech axle back exhaust, Performance spoiler
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10-23-2011, 05:07 PM	#17
Hix Enlisted Member 1 Rep 31 Posts Drives: 2009 Bmw m3 Join Date: Oct 2011 Location: Houston, tx iTrader: (0)	Thing about BMW comfort access is that it works some of the time maybe... Pretty much as long as I am in no hurry and nobody is around. The girl I was dating has a Murano with a similar setup and it always works the first time as soon as she the touches the thumb thing. Really annoying.
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10-24-2011, 09:14 AM	#18
Boostin FD Bored all the time 382 Rep 2,173 Posts Drives: Batmobile Join Date: Jan 2010 Location: Kirkwood iTrader: (2)	Same thing happens to me often... the other thing that bothers me is that the key fob won't unlock the car if you press the button, unless you are as close as 6ft. In my Audi, i could unlock the car from inside my apartment which is about 50 ft away. Yet with BMW, you have to be very close... I replaced the darn battery just past weekend. __________________ Current: 2014 991 Turbo RS Past: 15 GT3, 17 R8 SC, Two 16 M4 GTS’s, Two 18 GT350R's, Two 13 RS5’s, 13 M3, 10 R8, 15 M4, 09 M3, 04 M3, 09 S5, 02 M3... It all started with an RX-7 (FD).
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10-24-2011, 09:58 AM	#19
///My5UV Lurker 78 Rep 812 Posts Drives: YMB F80, SS E90 Join Date: Nov 2010 Location: Austin iTrader: (0)	Maybe some of you folks are in an area with alot of radio interference? I have noticed that the CA barely works if I have the key in the same pocket as my phone. __________________
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10-24-2011, 02:16 PM	#22
Mike van D Major 18 Rep 1,112 Posts Drives: SG X6 35i; MW e92 M3 Join Date: Jan 2011 Location: Germany iTrader: (0)	Know a couple of folks who had the CA not work right and had the door handle cover replaced...said it's fixed the problem so far. __________________ ...just enjoying life.
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