Key Fob/Battery issue

Mine only failed totally when it was late at night and all dealers closed, and I was in the basement of a store downtown.,... argj@Q#R*@#R.. it took two tow truck divers over an hour to get my bike out of that basement.... shit ! ! !
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🤣 Ain't that the 100% truth!

Mike
 
I'm having a similar problem with my 2021 R18 First Edition. Usually no problem during the first use of the key fob during the day. As the day goes on when I start the bike I get the red warning LED (looking for the key) and it takes a couple of pushes of the ignition button to get it to self-check. I also get the lost key warning while driving - it's usually intermittent and brief. My concern is I will end up stranded. I ordered and received a new fob from my BMW dealer - this one won't pair at all with the bike. Useless. Now I am dealing with the dealer who won't call me back to find out what to do with the useless new fob.
 
If I understand this right, if the battery in the FOB dies while I am in the middle of no where desert, there is no way to start the bike if I do not have the spare with me? Thats crazy, even toyota prius will let you put a dead FOB next to the push button to start the car if the battery goes dead.
 
If I understand this right, if the battery in the FOB dies while I am in the middle of no where desert, there is no way to start the bike if I do not have the spare with me? Thats crazy, even toyota prius will let you put a dead FOB next to the push button to start the car if the battery goes dead.
I've learned a lot dealing with this. The spare key AND the fob with a dead (or no) battery should work to get the bike started IF they are very close to the under seat antenna - like a couple of inches. The battery in the FOB serves only to extend the range of the connection so you can carry the FOB in a pocket. Otherwise, as with the spare key you'd have to (in my case) press it into the driver seat to get it close to the antenna. My issue is that even with a fresh battery the antenna sometimes does not detect the FOB in my pocket and often while driving it "loses" the connection and warns me that the key is not detected.
 
I've learned a lot dealing with this. The spare key AND the fob with a dead (or no) battery should work to get the bike started IF they are very close to the under seat antenna - like a couple of inches. The battery in the FOB serves only to extend the range of the connection so you can carry the FOB in a pocket. Otherwise, as with the spare key you'd have to (in my case) press it into the driver seat to get it close to the antenna. My issue is that even with a fresh battery the antenna sometimes does not detect the FOB in my pocket and often while driving it "loses" the connection and warns me that the key is not detected.
What seat do u have?
 
BMW sells 'em - but Mustang makes them. Wouldn't trade it for the stock seat - its pretty awesome. Spare key works but really have to press it into the seat. FOB issue did start after I got the seat - but lots of riders have the mustang w/o a FOB issue.
 
Not sure if this is helpful, but could be a way to isolate the issue to either the antenna or fob.
Fasten the spare key to the antenna, remove the seat, tape it, ziptie it or something, then pop the seat on and see if the problem occurs.
If the problem continues, then it would be the antenna, while if it resolved, would indicate the fob.
Hope this is useful for someone.
 
I've learned a lot dealing with this. The spare key AND the fob with a dead (or no) battery should work to get the bike started IF they are very close to the under seat antenna - like a couple of inches. The battery in the FOB serves only to extend the range of the connection so you can carry the FOB in a pocket. Otherwise, as with the spare key you'd have to (in my case) press it into the driver seat to get it close to the antenna. My issue is that even with a fresh battery the antenna sometimes does not detect the FOB in my pocket and often while driving it "loses" the connection and warns me that the key is not detected.
Oh ok, that makes me feel better, I took the spare and held it under the fender close to the seat and it did work, if I can do that with the regular FOB when the battery is dead I am fine. I have the regular r18, the 2022 model and last week I started the bike with the FOB on a table next to the bike and forgot to pick it up, I rode for about 8 miles before I looked and saw the indicator that the FOB was missing, I could have ridden as far as I wanted as long as I did not shut it off, the bike was running fine and I had gone almost 20 miles by the time I got back to my garage.
 
Maybe this will help. I had the same issue with my R18 FE in the beginning. Checked the key fob and bended the contacts a little bit towards the inside/ battery. After that, no more issues. It’s worth a try. Good luck.
 

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So, I decided to tear apart my key fob...

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This fob is actually quite easy to disassemble. There are four plastic nubs that must be clipped off that circle around the CR2032 battery. Once these are clipped, a plastic pry tool can be used to gently pry the key halves apart.

Teardown3.jpg

Here, I have my angled nippers and showing the four nubs, now clipped.

Teardown4.jpg

When the key half is removed, half of the circuit board is exposed, which shows the lock and unlock buttons, as well as the microchips and what appears to be an oscillator crystal. Note there are two additional plastic nubs that also hold the circuit board to this half of the key fob.

Teardown5.jpg

Removing the plastic nubs and gently prying the board out of the key fob casing exposes the other side of the circuit board. HERE's the locking resistors (??? on the actual name. I tried googling them to no avail.) that the onboard locking system "talks" to.

Thusly, I'm going to put my BMW "Bimmer" hat on here and talk briefly about the "EWS" system in their mid-1990's vehicles, and why I believe this is EXACTLY what BMW is still doing here, in 2022. Check out the following PDF screen grab:
Screenshot 2023-05-19 at 21.14.36.png

"L1" and "L2"silkscreened on the PCB (printed circuit board) indicate "inductors" ("L" is shorthand for...inductors). This full EWS PDF can be found at: http://www.unofficialbmw.com/images/BMW_EWS.pdf if you are so inclined to learn more about the basics of the EWS I through III system

Mind you, that the EWS system relies on the vehicle itself to provide power to the inductive coil to read/write the EEPROM on the key every time the engine is turned on.

On our bikes, the CR2032 battery (in my deductive opinion, mind you!, since we don't have service manuals...looking at you BMW...) would obviously be the power source to the EEPROM every time we turn the engine on. Post 44, by VARG, where he highlights the user manual where we must insert our key into the slot under our seat where our key ring is located reminds me of using the bike's power to energize the key's inductive coil to power the key's EEPROM, like this screenshot in the EWS:

Screenshot 2023-05-19 at 21.14.16.png

Note how the vehicle's ring antenna powers the key inductive coil? Look familiar? The old BMW keys didn't work outside of the key tumbler so there was no need to use the key's own battery to power the EEPROM, unlike our bikes.

Teardown6.jpg
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A couple high-resolution photos for anyone who wants to reverse-engineer the key fob ;)

Hope someone finds this useful.

Mike
 
Not sure whether this relates to anyone having this problem, but thought I'd share anyway - just in case.

I was getting the same warning, so raised it at the first service - when I picked up my bike, the tech told me he replaced the fob battery and everything was working fine, but to make sure I didn't leave the fob close to the bike when it's not being used.

Clearly, you carry the fob when you're riding - not an issue.

His comment related to leaving the fob in a bag on the bike, or close by in your garage.

His reasoning was, the loop and the fob "poll" eachother regularly (don't know how often). Apparently, and it makes sense, they don't do this when the bike's running. BUT, when not being ridden, if they're within radiowave reach of eachother, the battery in the fob will drain.

No problem since.
 
Thanks. This make a ton of sense - Ive been keeping the fob pretty far away. Actually scheduled a trip to the dealer to have them run a check for faults...got there (45 mile 1 way) and the service guys said BMW did a firmware update on their gear and they couldnt do it. Drove home. Awesome customer service. It hasnt left me stranded yet so I'm kinda getting used to it losing the key for a few seconds here and there. Only 2x has it taken me 3x punches of the igntion...
 
My dash started lighting up about the key(fob) a couple of months ago--I just replaced the battery and all was well.

I just thought was weird that the battery went out so soon---less than a year from buying it new----I mean I've had cars going on 6-7 years where the fob was still working and never replaced the battery and was working just fine when I traded in the car.

The fob is stored about a quarter mile away from the bike.
 
I havent been stranded yet and now that I've got more experience with it - I only had 2 really bad moments when it took 3+ button punches to get the ignition to work. My fob is stored 50 feet from the bike...so maybe that is causing a drain. Now I get a brief LED flash maybe 60% of the time and the bike will "lose" the key and warn me while driving - maybe 30/45 seconds at a time - seems random and occasional. Maybe this is "normal"? Glad you resolved it.
 
Another tip:

Carry several fresh name brand CR2032 batteries with you just in case. It'll save you the hassle of removing the seat and sticking the key directly into the key ring antenna slot to get the bike started ;).

I put mine in a ziplock bag in my side bag. An ounce of prevention...

Mike
 
Hi, just got my new R18 Classic, now a bobber... with 200 kms on the clock I was riding and the lost fob light came on. Got home and it recognised fob after stopping it and restarting.. talked to the dudes at Rogue whose bobber kit I got and Billy said what pocket did I have fob in, right, he said he has no idea why but fob in left pocket does not get that happening... so weird if receiver unit is under seat...anyway done a lot more kms on it since then in left pocket, no more probs....
 
yeah - learning. I don't think it matters which pocket - my issue hasn;t left me stranded - sone about 2K miles since. Sometimes is loses the key while driving - 30-45 secs at a pop multiple times...then a day like today and I did 150 miles with no issues. I think its just worse on some bikes than others.
 
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