"Key not in car" quite often

"Key not in car" quite often

I'm getting a "key not in car" message that stops me from starting the car quite often. This is especially annoying since the key was detected to unlock the car, and I can use the toggle on the key to lock/unlock the car while the message is displayed. How is that detection different from the detection that unlocks the car?

lilbean | 03/05/2019

I don’t know but it sounds like you need to replace the fob battery.

TranzNDance | 04/05/2019

A phone can block the fob signal. Do you put the fob next to a potential signal blocker in the car?

Silver2K | 04/05/2019

Believe it or not, your clothing can block the signal. I had a conversation about clothing design with a young lady and she explained a lot of clothing today have silver lined in the fabric.

When wearing my thin but extremely warm north face jacket, I get that message alot.

Go figure!

kerryglittle | 04/05/2019

Tinfoil keeps out the Gamma rays too Silver. LOL.

barrykmd | 04/05/2019

That's why Silver wears his special shorts - to avoid fob problems.

Silver2K | 04/05/2019


murphyS90D | 04/05/2019

Presumably you are talking about aluminum foil, I've never seen "tin foil". Gamma rays go right through aluminum foil. You need concrete to stop gamma rays.

jackrg | 04/05/2019

Thanks for your insightful comments, everyone ;) @TranzNDance I think you might be on to something - I'll try separating the key and my phone (they're usually in the same pocket).

lilbean | 04/05/2019

I agree with @TranzNDance. That happens to me.

jackrg | 04/05/2019

@lilbean I have changed the battery, and the problem also occurs (perhaps less often, I'm not sure because I usually drive when we're together) with my wife's fob so it seems like the fob itself isn't the problem. It just seems strange that the car can respond to signals from the fob (lock/unlock) and yet not think that the fob is in the car. Perhaps they need a place to set the fob (like the M3 key card).

murphyS90D | 04/05/2019

Transmissions from the cellphone block the receiver in the fob so it doesn't know the car is asking if it is still there.
The signal from the car to the fob is very low power. It only works within 3 or 4 feet. The signal from the fob to the car should work from 75 feet away from the car.

SoCal Buzz | 04/05/2019

RFID cards next to fob also cause the same issue.

carlk | 04/05/2019

That has happened to me a few times in the past. Not a battery issue. Moving the fob inside my pant pocket a little will always fix it. It usually lasted for a few days and then mysteriously gone. May be metal house keys had something to do with it but I wasn't too sure of that.

Charsiubao | 04/05/2019

@jackrg... are you sure you are talking about a Tesla? what toggle? Driving the Tesla without the fob (with just the mobile app) is a pretty normal alternative to using the normal that the 3 doesn't come with a fob/key like the S/X.

Silver2K | 04/05/2019

USB drives in pocket can cause this issue also. I carry them to do repairs and have similar issues

murphyS90D | 04/05/2019

Anything metallic that blocks the signal from the car to the receiver in the fob will cause the problem. Radio signals do not go through metal.

akikiki | 04/05/2019

jackrg, you say you replaced the battery. There's no guarantee that even a freshly unpackaged battery had not been sitting on a shelf long enough to drain to the same level as the one you took out.

And since you asked, there is a recommended location inside the car to place the fob. It first was in the center console cup holder, then revised to near where the front USB slots are. We just don't hear much recently.

lilbean | 04/05/2019

@jackrg My X fob was doing that. Come to think of it, when I brought it in for service, the firmware on the fob was updated and it didn't happen again.

kerryglittle | 05/05/2019

Theres firmware for the FOB lilbean? Never knew that. Would that be something they would only do at a SC?

jackrg | 05/05/2019

@TranzNDance Thanks! That seems to have done the trick. I started putting the phone and the fob in different pockets and in the couple days since then, I haven't gotten a single "key not inside" error.