What happens if Key Battery dies?

What happens if Key Battery dies?

Given that the Model S operates automatically off of the Key Battery, what will a driver do if the Key Battery dies. This happened to me once with a Lexus key fob. The battery died and I could not operate the car until I had replaced the battery. But what if you are out on a camping trip or someplace else remote where a replacement battery is unavailable. Is there a backup battery in the key fob? Is there someway to enter an "unlock" code into the car so you can start it? How do you open a door if the key battery dies?

Tesla may already have published the answers to these questions. If so, I would appreciate any links to pages that discuss this topic.

Thanks for your help

MandL | 2012年6月26日

My Kia fob has a pull out metal key to open the door (and glove box, so you can take it out when leaving the fob w/ a valet) and a key "dock" inside the center console that allows the push button start to work when the battery is dead.

I realize Tesla has solved the valet problem otherwise, maybe the Model S fob could have an unpowered RFID chip in it that can be read by placing it somewhere specific even when there is no battery power to send the door open signals? Something like a Zipcar card.

Theresa | 2012年6月26日

When I visited the dealership in Chicago I asked that question. They tried to show me how it worked but they were having several issues with the car that day. Suffice it to say they explained that by placing the key in an area by the right front wheel well the door will open. I didn't ask how it worked but I am assuming it is probably an RFID chip.

adstein | 2012年6月26日

That is similar to the Lexus which works just fine with a dead battery. You hold the battery over the push to start button and the car will start.

adstein | 2012年6月26日

I meant the key fob not the battery.

Timo | 2012年6月26日

I am assuming it is probably an RFID chip

RFID chip security is quite weak. If there is way to use that to gain access to Model S then it wouldn't be too hard to make "master key" that would open all Model S cars. It would need to be a bit more than just that. Maybe it was wireless charge point where key gets enough power to initialize proper encrypted data transfer between it and the car.

jbherman | 2012年6月26日

Could TM access/unlock and start the car for you remotely? Or, could there be an iPhone app that can operate the car via your iPhone in an emergency?

jerry3 | 2012年6月26日

There is a magic place underneath the front wheel well where you can place the fob-with-a-dead-battery and it will open the car.

Sudre_ | 2012年6月26日

Remember the hideaway key?
Just buy a new battery for your FOB in a year and duct tape the new battery under or somewhere outside the car so when the FOB goes dead you have a replacement battery ready.
I already used a backup battery once in the 13 years I have owned my car and it's just a push button alarm. It also doesn't leave a key and access to your car outside to be discovered.

dborn | 2012年6月26日

i hope battery replacement in the fob is easier than the same procedure in a Mercedes fob. You almost need a degree in engineering to do the job. The one time i have had to do it, looked up the net - that did help, but it won't if you have no internet connection and your fob goes dead, even if you have a spare battery. also, the job needs to be tool less, or again, you will be in trouble. It also won't hurt if the procedure is obvious. Your manual locked in the car won't help you...
At least Merc has a skeleton key in the fob which will unlock the car....

pilotSteve | 2012年6月26日

Is this covered in the owner's manual? (hint: when will a copy be posted here!!!!!!)

GeorgeA | 2012年6月26日

Hopefully Telsa has an easy but secure way of unlocking our car when the key fob battery runs out. I agree instructions should be in the manual. They probably are.

Does anyone know how many keys do we get? I hope at least two. If not, how much will it cost for a second backup key in case first key gets misplaced or damaged? I generally have 3 keys for each car. A key for myself, my wife and a hidden backup emergency one.

Is it impossible to lock this key in your car by accident?

Brian H | 2012年6月27日

Base Murphy's Law:
"It's impossible to make things foolproof, because fools are so ingenious."

olanmills | 2012年6月27日

I think that the phone app should be able to do this, perhaps with a setting within the car that allows you to enable or disable the feature.

jerry3 | 2012年6月27日

There is a magic place underneath the front wheel well where you can place the fob-with-a-dead-battery and it will open the car. (Posted again). This is in the Model S owners manual.

BYT | 2012年6月27日

Jerry, Have you seen the Model S owners manual? Can you share it??

jerry3 | 2012年6月27日

There are some screen shots in the TMC. One of the pages just happened to show that.

BYT | 2012年6月27日

Thanks, I plan to check it out but hope its all posted soon somewhere!

BYT | 2012年6月27日

Posted in its entirety I meant to say

jerry3 | 2012年6月27日

Me too. I would love to have the manual before delivery. I'd also like a new car features manual.

David70 | 2012年6月27日

Me too on the manual. I always try to download the manual of any computer or computer accessory before I buy it.

DallasTxModelS | 2012年6月27日

Use your smartphone app to open the doors.

BYT | 2012年6月27日

I hope we can also roll down all the windows and open te sunroof with the app as well

MandL | 2012年6月28日

From one of those screen shots of the manual - "press and hold to activate the express window down function" - talking about operation of the fob.

foto | 2012年6月28日

Do they give you access to the key fob before you get into the Test Drive car before you get into it? If so, would anyone kindly test the approximate range to operate the doors and most especially the express window.

I used to own a Nissan Altima and could lock and unlock the doors from about 150ft away and could operate the express window/sunroof from approx. 100ft even through walls. Ironically, my Mercedes Benz CLS does not perform as well. I need to be within 50ft to lock/unlock the doors and less than 5ft away from the driver-side door pointing the fob to the door handle to operate the express window/sunroof.

EdG | 2012年6月28日

Re: unlocking from a distance

Try putting the fob under your head, just ahead of the "wind pipe", touching. I've done experiments while walking away from a car and found that without this technique I couldn't lock the car, but with it (several steps later away from the car) I could. Nothing like using your head. For an antenna boost, anyway.

MandL | 2012年6月28日

@EdG - How big is the plate in your head? and is it titanium or some other metal? ;-)

EdG | 2012年6月28日

Fortunately, they haven't picked it up at the airport yet. Try it, you may find out yours is just as big as mine.

Most people I recommend this to are worried about radiation effects on their health. For some reason, they don't worry about AM/FM radio, neutrinos, etc. They generally do worry about cell phones but still talk on them. I tell them about the false notion, still being passed on, of high voltage lines and the fear of cancer:

When I was in graduate school, I passed by a photo of a girl smiling while her head was in a air gap through which a magnetic field of a gazillion Tesla passed. (I don't remember how big the field was, but at the time I was amazed people could manufacture a field that large. It was a HUGE number.) My conclusion was, and still is, if she wasn't killed instantly, little tiny cell phones and the like can't do diddly to your head.

You look a little funny doing this with your keys, though, so make it quick.

EdG | 2012年6月28日

Just in case someone wants to get 2 bits in, the units were probably quoted in gauss or even milligauss. Whatever.. I remember it as being way too big an electromagnet.

Timo | 2012年6月29日

Another way to boost the signal is to put it against your temple. I'm guessing your eyesockets work like tiny directional antennas and it boost signal to direction you are facing.

Brian H | 2012年6月29日

What they didn't show you was that 2 years later she looked like Elizasnezer Scrooge and sounded like Daffy Duck. Some things take time to confer their blessings.

EdG | 2012年6月29日

Could be. I guess I like to take risks - as long as my time here is finite.

BYT | 2012年6月30日

@MandL, thanks for that information. I loved that feature in my Honda Accord and so would miss it greatly in my Model S if it wasn't there. Of course, with constant temp. control in the Model S, I may not be worried about returning to a 120 degree car interior that I want to pop the windows open on.

GeorgeA | 2012年6月30日

akimball: Jerry3 posted: "There is a magic place underneath the front wheel well where you can place the fob-with-a-dead-battery and it will open the car. (Posted again). This is in the Model S owners manual."

olanmills: Besides opening car with smart phone, will it run car also I wonder? How can you start car with dead keyfob? akimball raises this issue also. If your cell is lost / stolen, hope we can reset code.

Brian H: Many vehicles will not let a person lock the car if they accidently left their keys in the ignition.

Does anyone know how many keys we get and how much for an additional one?

jerry3 | 2012年6月30日

My understanding is that once you place the fob in under the wheel well, you will be able to drive it because that turns on the car. On the other hand there may be another place inside the car to touch it, but no one has posted those manual pages--if they even exist. I believe that the Roadster works the same way.

You get at least two. There is no valet key because that function is in the software.

I've never heard a price for an additional one. Toyota charges about $200, so I would expect around the same price.

Mark42 | 2012年7月2日

I asked this question at my test drive. The tech assured me that even if the key fob battery dies, the car can be opened and operated by having the key fob close to the car. The car recognizes the key even with a dead fob battery. The car will not let you lock the keys inside. This is good most of the time, but if you are into outdoor sports, water sports, or want to put an emergency key somewhere on or near the car, you really cant. The car will recognize the key and unlock the car. There is no "plastic key" or other emergency key. In my current vehicle, I lock my keys in my car and use a keypad on the door which I installed to enter the car. I also have a trailer hitch that has a tiny safe inside which can hold a key. I dont see any options here for the model S and hope they an arrange somethin that works. I didnt think this was going to be a big deal, but it just might be a deal breaker if I cant use my car to do the sports that I love.

Brian H | 2012年7月2日

Wrap it in aluminum foil?

EdG | 2012年7月2日

Take the battery out and wrap it in foil.

Brian H | 2012年7月3日

Blocking the passive RFID response is the issue.

pilotSteve | 2012年7月3日

My BMW 550 has the 'comfort access' option, which is their name for the remote lock/unlock and car start with the key in proximity. One of my favorite features (along with the HUD)!

One thing: when washing your car you need to take the key out of your pocket and leave it inside (20-30 feet away) or every time you touch the door handles, etc. the car will lock and unlock.

BMW claims you can't lock the car with the keys inside (or in the trunk, etc.) and it has never happened to me but there are posts on that owner's forum claiming it can be fooled. Over all a great feature and on that made the "tech package" a must-have for me.

Roblab | 2012年7月3日

At present the dead key fob will unlock the car if placed just behind the passenger side front wheel. RFID works at about one foot. Once inside the then opened car, the dead key fob is placed near the front of the driver's seat cushion, which will start the car. A key in the pocket would most likely be withing RFID range.

As far as doing sports, don't people have lockers for changing into sports clothes? The key fob in the locker would not be detected by the car. For scuba or kayaking, why not double zip lock bags, and squeeze the air out? In our lab we use bags that are air tight, which is a step above water tight.

Brian H | 2012年7月4日

If you lose the bag underwater, fleeing a giant squid or parrot fish, you're "", blued, and tattooed!

Vawlkus | 2012年7月4日

How about an RFID patch? Stores use that for inventory tracking, so just marry that to a smokers patch type application. Then you can open your car and start it with a wave of your hand :D

Timo | 2012年7月4日

Put it under your skin in the back of the hand and Demolition Man -era has arrived :-)

It's a bit funny that low budget scifi comedy/action manages to show close future that accurately, and big blockbusters fail miserably. I wonder when those three seashells appear in bathrooms...

digitaltim | 2012年7月4日

I would gladly take an implant if I could use that to wave over scanners to ID myself...chip me!

I have been pushing for this for years at my company.

bsimoes | 2012年7月4日

It's funny because I just thought of this and put it on another thread, but we now have finger scans; that's how I log on to my computer. I don't think we need to get drastic and have implants--ooh, that doesn't sound good!

cerjor | 2012年7月4日

Push on the front of the fob, the trunk opens. Push on the back, the trunk opens. What will open when the fob is in my Jean's pocket and I bend over?

Timo | 2012年7月4日

I gladly take implants if they somehow expand my abilities. Cyberpunk-era is not that far either. I just read about guy with both legs amputated under the knee that run 100m under 11 secs with prosthetic legs (South African Oscar Pistorius goes to Olympics to run 400m and 4x400m in their team. After Olympics gets to paraolympics and does 100m, 200m, 400m and 4x400m).

It doesn't take long before synthetic surpasses biologic. Just get "internet" inside your head with access to anyones experience and skills and "resistance is futile, you will be assimilated".

digitaltim | 2012年7月5日

@Timo - real RAM hardwired in and ready to be is not that far away at all.

Brian H | 2012年7月6日

I wonder how flash updates will be done ...

Brian H | 2012年7月6日

(I assume it would have to be non-volatile. Otherwise, fragmentation would render it non-functional in no time!)