When both key fobs suddenly won't work (with possible fix)... 2017 Model S

[jkautz]

Hopefully someone finds this helpful. I have a 2017 S P100D with about 49,000 miles on it. Long story short, suddenly both key fobs stopped working one day at the same time, though the car would run fine with the app. Soft restart didn't help (both buttons on the steering wheel and brake pedal), and replacing both batteries in the key fobs didn't make a difference. Initially made a service appointment (I'm out of warranty, so $212 was the quote for a fob replacement; still think the service app is a bot...). However, the more I thought about it, it just seemed weird that both keys would die the same day. Eventually that lead me to try to do the key fob update (under the service menu), and the car told me both key fobs were up to date, which seemed to indicate that the key fobs were working to some extent.

Anyway, end conclusion, wound up turning the car off under the safety menu, pulling off all the HVAC plastic bits in the frunk that cover the battery (three large pieces, I have the large HEPA filter), pulled the "big" battery connector safety plug, and then pulling off the negative battery cable. Gave it 2 minutes. Put it all back together, and it is working fine now. Not sure if that is considered a "hard" reset, but hopefully someone who was just as frustrated as I was finds this helpful and potentially saves themselves a service call.

 

[NewbyMaybe]

The wheel configuration reset on the service page might work if it happens again.

 

[5StarAdvisor]

Seriously?! I just tried replacing a battery and also had a problem… tried the old one and apparently there was enough juice to open the doors but not start the car. I confirmed the old and knee batteries were the same size. The second remote I relied didn’t have the battery because apparently I tried to replace it a few years agai and just gave up and started using the other one.
-I’m tempted to try your trick however I wish I could confirm that seriously this is what needs to be done; it makes no since.

 

[5StarAdvisor]

So I took it to SVC and one guy wanted to sell me a new remote… another guy said let’s try replacing the battery again. It worked!

The battery I put in was brand new from CVS, Tesla swapyot for a Duracell… they said they like Duracell even over Energizer. -Sounds crazy, huh?

 

[KalJoMoS]

-I’m tempted to try your trick however I wish I could confirm that seriously this is what needs to be done; it makes no since.

There is no trick, this just makes deep restart shutting down all running computers. As this menu does change the wheel settings - both on the car and the app then it’s advisable to change the actual wheel size back after the reboot.

 

[EVChris]

So this happened to me as well. I couldn't OPEN the car with the FOB. I swapped in new batteries into both FOBs and neither worked. Then I saw this thread and changed the wheel size, reset, changed it back, reset. The reset actually takes longer than you think. The car is up and running and then you finally get a reset complete message a few minutes later.

Anyways, this improved things. I still can't OPEN the car from the FOB. Instead I have to OPEN the car from the APP. But then I can drive the car (without starting the car from the APP). When I'm inside the car and the car is ON, I can open the frunk with the FOB which means the FOB is working; the battery is good; and the FOB is recognized. Also, I couldn't update the FOB at the console.

I'll keep working the problem. This would definitely be a problem going somewhere where there wasn't cell coverage.

Also, lately windows have been opening (not all the way) when I start the car.

 

[EVChris]

Unsurprisingly, the problem is the same for the charge port.
But I can also open the charge port from the app.
Also, this was out and about at a Supercharger.
So the problem is NOT local to the garage.

 

[EVChris]

Holding my FOB in the middle top of the rear window and pressing OPEN reliably gets the car open.
But it doesn't get the car to start.

 

[dsm363]

So this happened to me as well. I couldn't OPEN the car with the FOB. I swapped in new batteries into both FOBs and neither worked. Then I saw this thread and changed the wheel size, reset, changed it back, reset. The reset actually takes longer than you think. The car is up and running and then you finally get a reset complete message a few minutes later.

Anyways, this improved things. I still can't OPEN the car from the FOB. Instead I have to OPEN the car from the APP. But then I can drive the car (without starting the car from the APP). When I'm inside the car and the car is ON, I can open the frunk with the FOB which means the FOB is working; the battery is good; and the FOB is recognized. Also, I couldn't update the FOB at the console.

I'll keep working the problem. This would definitely be a problem going somewhere where there wasn't cell coverage.

Also, lately windows have been opening (not all the way) when I start the car.

Have you had service look into it? I had a brand new key fob on my Dec 2023 Model S stop working. I went through 3 batteries in a month until I finally had them look at it and they replaced it for free. For an older car there might be cost involved but unlikely to have both key fobs broken.

 

[EVChris]

Have you had service look into it? I had a brand new key fob on my Dec 2023 Model S stop working. I went through 3 batteries in a month until I finally had them look at it and they replaced it for free. For an older car there might be cost involved but unlikely to have both key fobs broken.

It started working again. I think the problem was caused by interference from the next car over in my parking garage. It is recently new and now recently gone. It seems sort of like the Mt Wilson case mentioned in other threads.