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Locked out of Model X - Both Key Fobs not working

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This past Friday I become locked out and stranded outside my Model X while parked alongside a strip mall in the late evening. A few days prior to this incident, the first of my two key fobs generated a "Key not inside car" message, and so I left the first fob at the house and grabbed the second one for this trip. This was just after replacing both batteries with new ones obtained from Amazon a few days earlier. This second key fob worked well into the evening so that my dog and I could make the rounds picking up a few items for the house. At about 8:00pm I hopped into my car after a quick visit to the hardware store and noticed that again the second key fob was causing the car to generate a "Key not inside car" message. I noted that this could become a problem and wondered if there was something wrong with the car's receiver as I had just replaced the batteries in both fob's.

I did not find what I was looking for at the hardware store so I set off to visit another. When I arrived at next store it looked like it may be closed, so I parked along side the strip mall and quickly hopped out to view the hours on the door. When I walked back I found I was locked out with my phone still in the car and the dead key fob inside my coat pocket which was also in the car and alongside the dog. I walked to the nearest open store and was grateful to find a cashier who let me borrow her cell pone to call Tesla roadside service. I selected the "locked out" assistance option but two calls to two different people at this number resulted in no one willing to remotely open the car for me, and so I walked 2 miles home and 2 miles back to get my first key fob and another new battery - with no coat at 32 degrees F (thank you Audrey).

The next day, I purchased four new batteries from a retail store thinking that I received a bad batch of batteries off of Amazon. I replaced the batteries again in both key fobs while inside the car. The car seemed happy at this point. Later on, into the evening I again received a "Key not inside car" message while having both fobs with me with the newly replaced batteries. This was odd, and I drove immediately home.

Once home, I cracked open both fobs, and with a new battery measured the current draw on each using a multimeter. The meter displayed a continual 38mA draw from each of the fobs. The Panasonic CR2354 battery has a 560mAh rating, meaning that a new battery would last round 14.7 hours at this current draw. What's going on?

I've scheduled a mobile service visit to fix this issue and they responded with an estimated cost to replace the batteries. I think the issue is with the fobs, not the batteries. Both fobs at the same time after no issues for two years? Has there been a software update to the fobs recently?


20210301_092528[1].jpg
 
If you think the fobs are bad you can take them to the Service Center for replacement or reprogramming.

However, it might be some bad batteries. If you look at the reviews on Amazon the retailers that sell multiple batteries cheaply have some poor ratings and the battery quality is usually bad. Same issue with batteries from some stores. The last place I bought from sold them for $14 each. They have been working for a year.

If you do have your fob handy, in the manual there is a procedure for getting into the car and driving it with a dead fob battery. It is on Page 16 of the manual. One thing they do not mention is that you need to hold the key in the spot on the door for seconds, and may need to move it to a few spots before it works and hold it for a few seconds in each spot. You may also need to leave the fob for a minute or so by the 12V outlet to drive the car.
 
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The meter displayed a continual 38mA draw from each of the fobs.
If you think the fobs are bad you can take them to the Service Center for replacement or reprogramming.

However, it might be some bad batteries. If you look at the reviews on Amazon the retailers that sell multiple batteries cheaply have some poor ratings and the battery quality is usually bad. Same issue with batteries from some stores. The last place I bought from sold them for $14 each. They have been working for a year.
Bad batteries wouldn't explain the 38mA draw he referenced tho.

Aside1: Amazon batteries I purchase and have in my glove box: https://smile.amazon.com/gp/product/B00KFSX8KQ

Aside2: I've put these images in my cloud for access (if I have my phone; OP obviously didn't).
Re: You may also need to leave the fob for a minute or so by the charge port to drive the car. -- you mean 12v power outlet I think per manual.
IrMnTg0.jpg
iryEUqD.jpg
 
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Bad batteries wouldn't explain the 38mA draw he referenced tho.

Aside1: Amazon batteries I purchase and have in my glove box: https://smile.amazon.com/gp/product/B00KFSX8KQ

Aside2: I've put these images in my cloud for access (if I have my phone; OP obviously didn't).
Re: You may also need to leave the fob for a minute or so by the charge port to drive the car. -- you mean 12v power outlet I think per manual.
IrMnTg0.jpg
iryEUqD.jpg
Oops 12V outlet is correct. I updated my post. Thanks.
 
This past Friday I become locked out and stranded outside my Model X while parked alongside a strip mall in the late evening. A few days prior to this incident, the first of my two key fobs generated a "Key not inside car" message, and so I left the first fob at the house and grabbed the second one for this trip. This was just after replacing both batteries with new ones obtained from Amazon a few days earlier. This second key fob worked well into the evening so that my dog and I could make the rounds picking up a few items for the house. At about 8:00pm I hopped into my car after a quick visit to the hardware store and noticed that again the second key fob was causing the car to generate a "Key not inside car" message. I noted that this could become a problem and wondered if there was something wrong with the car's receiver as I had just replaced the batteries in both fob's.

I did not find what I was looking for at the hardware store so I set off to visit another. When I arrived at next store it looked like it may be closed, so I parked along side the strip mall and quickly hopped out to view the hours on the door. When I walked back I found I was locked out with my phone still in the car and the dead key fob inside my coat pocket which was also in the car and alongside the dog. I walked to the nearest open store and was grateful to find a cashier who let me borrow her cell pone to call Tesla roadside service. I selected the "locked out" assistance option but two calls to two different people at this number resulted in no one willing to remotely open the car for me, and so I walked 2 miles home and 2 miles back to get my first key fob and another new battery - with no coat at 32 degrees F (thank you Audrey).

The next day, I purchased four new batteries from a retail store thinking that I received a bad batch of batteries off of Amazon. I replaced the batteries again in both key fobs while inside the car. The car seemed happy at this point. Later on, into the evening I again received a "Key not inside car" message while having both fobs with me with the newly replaced batteries. This was odd, and I drove immediately home.

Once home, I cracked open both fobs, and with a new battery measured the current draw on each using a multimeter. The meter displayed a continual 38mA draw from each of the fobs. The Panasonic CR2354 battery has a 560mAh rating, meaning that a new battery would last round 14.7 hours at this current draw. What's going on?

I've scheduled a mobile service visit to fix this issue and they responded with an estimated cost to replace the batteries. I think the issue is with the fobs, not the batteries. Both fobs at the same time after no issues for two years? Has there been a software update to the fobs recently?


View attachment 640996
This is bizarre. Essentially the same thing happened to me yesterday with my 2016 Sig X (yours is a very recent post.) Replaced several batteries with no effect, including one packaged and given to me by Tesla a few months ago. My other key fob stopped working after I dropped it in water, so I don't have that back up.

I replaced my MCU several months ago and noticed that the IOS application will lock the car but won't unlock it. To my surprise, I just found out that the keyless start feature doesn't work either. The message to put on the brake to start car appears on the screen, but the car doesn't start. So I'm really screwed. I've tried placing the fob in the "right" spots and so far no joy. No 12V battery warnings and it was replaced 4 months ago.

But my MAIN reason for posting is how frustrating it is to get Tesla's attention. Can't call any one. Putting this into scheduler with lots of descriptions scored me an appointment in 9 days! And when I entered the problem in Roadside Assistance last night, no one has bothered to call or text me. Love the cars, love the stock/company, love the service when it happens, and HATE HATE HATE their system for dealing with incapacitating problems. When my MCU failed, I was unable to drive the car for a month, waiting for them to respond and help.
 
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@sevengables, You mentioned that no one at Tesla would unlock your car. Was that because the security questions that they asked to verify you were who you said were not answered to their satisfaction?

When the store clerk loaned you her phone, it didn't occur to ask to download and install the app on that phone? Just a login and unlock away, then delete the app so no one could use it after you. ??

It would be a wise idea to invest some time browsing and reading all the "locked outa my car" threads here to pickup tips on what to do when this happens.
 
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I replaced my MCU several months ago ... The message to put on the brake to start car appears on the screen, but the car doesn't start.
Aside -- after getting my MCU replaced (I assume you mean MCU1->MCU2) ... my car does not wake up with the brake after using the 'Power Off' menu option. I need to open the door despite having the press brake msg.
 
Replaced several batteries with no effect, including one packaged and given to me by Tesla a few months ago.
Possible problem. See thread post below. TL;DR "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."
Key fob not working after battery replacement
 
After posting, I found yet another battery in my drawer (from Amazon). 3.4 volts on meter. Put it in and the car immediately started. I left the car to move my wife's car out of garage to make room, came back to the car and it failed again. This happened once yesterday with one of the batteries. Started the car once then failed. So either really bad batteries, or the fob is bad and somehow sucking all the juice out quickly.

The good news, I saw the info on using key as RFID device, found the spot, waited about 30 seconds and sure enough, the car started. So at least I got it in the garage and can charge.

Still need to figure out why the keyless start and unlock on the ap stopped working. Related to new MCU or something else?
 
@sevengables, You mentioned that no one at Tesla would unlock your car. Was that because the security questions that they asked to verify you were who you said were not answered to their satisfaction?

When the store clerk loaned you her phone, it didn't occur to ask to download and install the app on that phone? Just a login and unlock away, then delete the app so no one could use it after you. ??

It would be a wise idea to invest some time browsing and reading all the "locked outa my car" threads here to pickup tips on what to do when this happens.

@Akikiki, Well you touched upon a bit of a sore spot with that question. Apparently I did not get all of the security questions answered correctly, because I myself had no way to reference them. In addition to my scenario "being too unique" to believe, I most undoubtedly know what my name is, I could tell her my email address, and I could read the VIN number using the phone's screen dim light. However, when asked the month and year I purchased the car, I (after looking later) missed the purchase month by one. I also know what the last service visit was for . . . but I don't know what month it was in. I also (obviously) could not tell her what the odometer read.

Now, how many people in the general public can tell you the year and month they purchased their car when they've owned it for two years? How many people in the general public can tell you what month your last service visit was in? So Audrey, determine I wasn't creditable enough, and kept pressing me to use my email to receive her communication after I explained to her my phone was in my car. Audrey at roadside assistance, where they have a "locked out" option, didn't bother to ask what the car's name was, she didn't bother to ask what my address was, she didn't bother to ask specific's that a company offering roadside lockout assistance would need in order to verify a owner to help in a lockout situation. She chose to not to act in a capacity that she was tasked to do while on the other end of a Roadside Assistance line with a "locked out" option. She chose to let me freeze, walk four miles and advised me to call a tow truck as her computer mouse hovered over the unlock button as she sat in her isotonic office chair.

Now, to address your question regarding the store clerks phone . . . she already extended herself by letting an unknown man walk out of the store she works at, at night, with her iPhone to walk a half a block away to answer Audrey's VIN question. I own a Android, I do not know how nor would I ask a clerk who's on the job to install software on her phone for a doof who has an expensive car that don't work.

As to the time I will invest for free: I will invest my time for free to diagnose and look into the 38mA current draw issue. I can then advise those who are following my original post while they invest Their time looking to solve why they had to call a tow truck despite changing fob batteries multiple times.
 
I hope my tone is more sympathetic. I understand how frustrating that must have been. I guess the only way to know if the store clerk would have said no to - install the app on her own phone would have been to ask. You were honest enough to return her phone after being a distance of a half block away; that likely would have been sufficient time to install, login, unlock, delete the app and hand the phone back. I guess it wasn't worth that 4 mile walk.

You can take some satisfaction in posting your event that others that read it before they are locked out, will gain some insight in what to try or not. Can't speak for the X, but we often see on the S, that even when the phone and fob are locked inside the car and the doors will not present, we can go to the back and open the trunk. I mention this only for anyone with an S that find themselves stuck outside.

There's many threads here on TMC about being locked out of cars. Also seems like those of us that offer help are criticized. But that's okay, we still offer the results of our own experiences in the hope that others at least mildly curious of the threads have avoided lockouts from our suggestions of prevention or alternatives.
 
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@Akikiki, installing the app on someone else’s phone had always been my backup plan of what I would do if locked out without my phone and no way to contact a family member with it on their phone. But since 2 factor authentication became an option last Fall, and I have implemented it, I would need my phone to authenticate that new login. I prefer the security of this, yet it does potentially limit me getting to my own account on a different device.
 
MCU1->MCU2 upgrades require some kind of security registration on Tesla's part. Otherwise you can't unlock or start the car. SC's can be sloppy about doing this. Anyone with this problem should contact Tesla to get it fixed. It does not require a mobile or SC visit to fix.

A remote possibility for the fab problem would be a malfunctioning button. That would probably keep the fob active all the time. A little harder to believe two fobs having that problem, but if they are both used by the same owner treating them the same way it is not out of the realm of possibility.
 
MCU1->MCU2 upgrades require some kind of security registration on Tesla's part. Otherwise you can't unlock or start the car. SC's can be sloppy about doing this. Anyone with this problem should contact Tesla to get it fixed. It does not require a mobile or SC visit to fix.
Unclear what exactly/specifically you are referring to with the underlined?
Are you talking about your fobs not working when you go to pick up your car after the MCU1->MCU2 upgrade? Seems like this is immediately obviously
Are you talking about the phone app not being able to start the car?
 
The issue described is not limited to MCU1>MCU2 upgrades. It also can occur with daughterboard and MCU1 replacements. We likely would not know if they had forgot to enable the security certificates for using the fob, else they would not be able to move the car to the parking lot after they finished working on it. I believe what you are referring to is enabling the security certificates so the car can be locked/unlocked and started via the app. That part they have been able to do remotely.
 
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This past Friday I become locked out and stranded outside my Model X while parked alongside a strip mall in the late evening. A few days prior to this incident, the first of my two key fobs generated a "Key not inside car" message, and so I left the first fob at the house and grabbed the second one for this trip. This was just after replacing both batteries with new ones obtained from Amazon a few days earlier. This second key fob worked well into the evening so that my dog and I could make the rounds picking up a few items for the house. At about 8:00pm I hopped into my car after a quick visit to the hardware store and noticed that again the second key fob was causing the car to generate a "Key not inside car" message. I noted that this could become a problem and wondered if there was something wrong with the car's receiver as I had just replaced the batteries in both fob's.

I did not find what I was looking for at the hardware store so I set off to visit another. When I arrived at next store it looked like it may be closed, so I parked along side the strip mall and quickly hopped out to view the hours on the door. When I walked back I found I was locked out with my phone still in the car and the dead key fob inside my coat pocket which was also in the car and alongside the dog. I walked to the nearest open store and was grateful to find a cashier who let me borrow her cell pone to call Tesla roadside service. I selected the "locked out" assistance option but two calls to two different people at this number resulted in no one willing to remotely open the car for me, and so I walked 2 miles home and 2 miles back to get my first key fob and another new battery - with no coat at 32 degrees F (thank you Audrey).

The next day, I purchased four new batteries from a retail store thinking that I received a bad batch of batteries off of Amazon. I replaced the batteries again in both key fobs while inside the car. The car seemed happy at this point. Later on, into the evening I again received a "Key not inside car" message while having both fobs with me with the newly replaced batteries. This was odd, and I drove immediately home.

Once home, I cracked open both fobs, and with a new battery measured the current draw on each using a multimeter. The meter displayed a continual 38mA draw from each of the fobs. The Panasonic CR2354 battery has a 560mAh rating, meaning that a new battery would last round 14.7 hours at this current draw. What's going on?

I've scheduled a mobile service visit to fix this issue and they responded with an estimated cost to replace the batteries. I think the issue is with the fobs, not the batteries. Both fobs at the same time after no issues for two years? Has there been a software update to the fobs recently?


View attachment 640996
Just curious how this issue was resolved? I measured the current draw on both of my key fobs, while a distance away from the car, and it was less than a mA. I am not sure of the system used if there is some period of sync or polling, but clearly a continuous 40mA or so will not work. Reading the thread, it seemed as if it got off track and your original question was never answered.
 
I have been having the same problem with both my key fobs. (TESLA X 2016 90D)
I had tesla service change the batteries on both my key fobs and it worked well for 1-2 days then failed.
I do have a SC app. tomorrow will update with the progress I still have to do the MCU1 replacements.
(according to the SC theses problem are unrelated).

On a side note Man the Tesla Service Centers has gotten really bad. Lets see what happens.
 
I have been having the same problem with both my key fobs. (TESLA X 2016 90D)
I had tesla service change the batteries on both my key fobs and it worked well for 1-2 days then failed.
I do have a SC app. tomorrow will update with the progress I still have to do the MCU1 replacements.
(according to the SC theses problem are unrelated).

On a side note Man the Tesla Service Centers has gotten really bad. Lets see what happens.
@PILOT RAVI Having a similar problem. What ended up being the problem and solution?