-
Want to remove ads? Register an account and login to see fewer ads, and become a Supporting Member to remove almost all ads.
I had the same thing happen to my key fob. I am about 150 miles from the nearest service center, and had literally just had my annual service done a few days prior when it happened, so I was really trying to find a solution without going all the way back to service. Finally stumbled upon a site in Ukraine that shows there is a weak point between the battery connector and the board that sometimes breaks when putting the new battery in.
I hit this with a small dab of solder to bridge the battery connector and the board test point/trace, and the key started working again.
Hopefully this helps someone save some time/money in the future if they have the equipment/ability to fix this themselves.
I hit this with a small dab of solder to bridge the battery connector and the board test point/trace, and the key started working again.
Hopefully this helps someone save some time/money in the future if they have the equipment/ability to fix this themselves.
Yep that’s what I did and it worked for me.
yep this worked for me as well.
I had a similar problem just recently with my Model S. The batteries in both my fobs were getting low, so I went to replace one (even used the recommended Panasonics) and post-replacement, the fob wouldn't work no matter how many batteries I put through it.
I put in the Energizer from the other low-battery fob and it started working again. Looking closely, the ground pad on the Energizer sticks out further than the Panasonic (and Duracels that I also got thinking I had a bad batch of batteries). On the outside edge of the ground spring pad that lays down underneath the battery, there was a bit of metal sticking up where you'd normally pry the old battery out. This was apparently shorting out any shallower battery I put in there and killing them within an hour or so. A little adjustment with a screwdriver and both fobs work good as new with any of the batteries I had on hand.
I suspect it's relatively easy to pry up that little piece when removing the old batteries, so that's probably what did it and is why removing the old battery "kills" some of these fobs.
I put in the Energizer from the other low-battery fob and it started working again. Looking closely, the ground pad on the Energizer sticks out further than the Panasonic (and Duracels that I also got thinking I had a bad batch of batteries). On the outside edge of the ground spring pad that lays down underneath the battery, there was a bit of metal sticking up where you'd normally pry the old battery out. This was apparently shorting out any shallower battery I put in there and killing them within an hour or so. A little adjustment with a screwdriver and both fobs work good as new with any of the batteries I had on hand.
I suspect it's relatively easy to pry up that little piece when removing the old batteries, so that's probably what did it and is why removing the old battery "kills" some of these fobs.
I having this same issue - low key fob warning and doens't work at all after battery replacement. Worse yet I had the dumb idea to try swapping batteries with the other fob and now neither fob works! To top it off the app is acting wierd and says unlocked but the car is clearly unlocked. I can enable keyless driving and roll down the windows to somehow get in but this doesn't seem like a great way.
I've put in for mobile service - luckily they can be here in 2 days on monday - would mobile be able to fix all these (Keyfob v1.0 Late 2016 Modes S). I'm going to check the contacts as suggested by the post above. If I didn't have another car I'd be stuck completely at home!
I've put in for mobile service - luckily they can be here in 2 days on monday - would mobile be able to fix all these (Keyfob v1.0 Late 2016 Modes S). I'm going to check the contacts as suggested by the post above. If I didn't have another car I'd be stuck completely at home!
Ostrichsak
Well-Known Member
update: I tried removing and repositioning the battery while standnig outside the car with both fobs, someone mentioned the contacts to check they hadn't lifted up causing shorts etc. Anyway both fobs are working! Not sure exactly what I did
Silicon Desert
Well-Known Member
I don't think there is even an annual service for any Tesla any more. At least that is what they told me about my car when I went in for the HW3 upgrade a few months ago. The car is almost 4 years old and never been in for annual service. They keep telling me it isn't needed yet.
Replaced battery in a key fob after low battery warning and it stopped working. So I’ve been using a different key fob for the past few months. Had to replace that battery and it stopped working. I often work in electronics so this isn’t user error—it’s just poor design. Now I’m going to miss two days of out of town work while I wait for a service appointment. Why hasn’t Tesla fixed this issue by now?!
Opticron,
That was it.. Thank you for your post. You solved my frustration. Now I understand why both of my Key Fobs stopped working at the same time. I replaced the battery on both fobs by using the same method of prying the old battery with my pointy knife. This caused the bottom battery ground Contact to lift up and touching the Positive side of the battery, which caused a shortage (like you mentioned). After I flattened the Ground Contact, now it works again.
I have to admit, it's a bad design.
I thought I had same problem. However when I took new battery back out I noticed there was a label on underside of battery
once label removed and battery replaced all was working again… Whew…This is 100% the problem here. I did a lot of work around this.I had the same thing happen to my key fob. I am about 150 miles from the nearest service center, and had literally just had my annual service done a few days prior when it happened, so I was really trying to find a solution without going all the way back to service. Finally stumbled upon a site in Ukraine that shows there is a weak point between the battery connector and the board that sometimes breaks when putting the new battery in.
I hit this with a small dab of solder to bridge the battery connector and the board test point/trace, and the key started working again.
Hopefully this helps someone save some time/money in the future if they have the equipment/ability to fix this themselves.
I have a 2019 MX Raven. I have 2 keys. Only I really drive it. After about 2 years I got the low battery warning so changed the battery. Then the key stopped working. I switched to the other key which was largely unused. It worked fine for about 6 months and then it's battery was low. Changed the battery same thing again. The same thing to happen on 2 keys is too much of a coincidence, there had to be a common problem here. Some buttons worked better than others, the side door buttons tended to be more reliable with the roof press being the worst. The proximity to the drivers door still seemed to largely trigger the door to open. This patter is a symptom of the underlying problem here.
The issue is this: the connection of the battery to the circuit board is too weak. That's the part circled red in this other person's post. when you remove the battery you push it up therefore exerting stress on this connection and ultimately breaking the connection. See photo one below, you will see in the gold ring there is a crack which prevents the power from the battery reaching the circuit board. One the reverse of the board at this very same point is the button for the lock/unlock - the roof button. Therefore, when you clock the roof button you are exerting force again directly on this connection and it forces this crack open. So even if the crack is allowing some power through, when you push the roof button it opens the crack and stops the remote working. This is the reason that some of the other buttons (side) and the proximity to work.
The solution is relatively simple but require you to fix this crack. It is done by a bit of soldering. I ordered a solder kit from Amazon for $25. This is compared with the price of a key of $320 from Tesla Service ($640 is you replace both keys). There's stuff on YouTube about soldering and the kit I got from Amazon has a practice circuit board.
Amazon.com
It is a little tricky. These photos are zoomed really close in, it's a really small hole. I managed to get a little solder in the hole and used solder flux to cover the piece too (see below). Did the same on both keys and they now work perfectly, as if new.
So essentially, this is a design flaw in this key. The weak connection point coupled with the location of the button on the other side means power will not flow to the key from the battery unless you make this repair.
It's nothing to do with the quality of the battery, or changing it in the car rather than the house etc. (although none of this does any harm).
I didn't see this - I found the problem to be something slightly different; Key fob not working after battery replacement
JerylCook
Member
tried everything under the sun when my mx fob stopped working... after numerous threads and articles... this did it... a $6 amazon solder kit and an ugly attempt later... it works... lol
thx to the all the folks who posted pics photos makin this an ez effortless fix...
thx to the all the folks who posted pics photos makin this an ez effortless fix...
Attachments
Last edited:
2 years later - one fob has now just plain stopped working - Model S 2016 (late) build - tried for several days of battery various brands checking the contacts. Seems to either have died or what not sure
THANK YOU!! This worked for me as well! I guess when I pried out the battery, I also pried the edge of the thin metal, that caused it to short (I used the same energizer battery that was that was already in there). I used a small screwdriver and pressed down the metal contact and it worked! If that didn’t work, I would‘ve tried putting a small piece of electrical tape on that section of the contact.
On a side note, I avoid Duracell button-cell batteries (and all Duracell batteries for that matter) because they have a bitter coating on it so kids don’t swallow it. The coating makes the battery not work with Apple AirTags. I wouldn’t want to have another complication replacing my Tesla remote battery.
Link discusses coating: Duracell CR2032 won’t work with Air Tag - Apple Community
Similar threads
- Question
