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12V battery requires Service

12V battery requires Service

I had the "12v battery requires service" message last Monday and it died 5 days later. My mobile service appointment was not until Wednesday the following week and my garage was filled with rotten egg smell by the 6th day so I decided to replace it myself. The battery costed $165+tax. The youtube video from Ohmmu provided good guidance on how to do it. The tricky part was pulling the battery out of the tight spot with wires in the way.

This is my second 12v battery replacement less than 2 years after the first one done under warranty (about 2 years from purchase). The weather is hot around here (Phoenix) so it might be the contribution factor. I'm curious if other owners in hot areas have similar issue.

TeslaTap.com | 19. august 2019

Heat might be a contributing factor, but I've heard that driving very little is actually more stressful on the battery. So if you drive 6-8 K miles a year, that might explain it. If you're up in the 12K+ range, well, that theory is toast :)

tommystus | 19. august 2019

I'm in the 12K+ per year.

jjgunn | 20. august 2019

I've had mine for 14 months & driven 33,000 miles -- no-issue with 12v battery but I do carry an Ionizer Charger just in case it needs a jump.

It works too because I helped a Model S that was dead get just enough juice in the 12v to be able to start the battery pack & SuperCharge.

MarinDon | 21. august 2019

Here's how I killed my 12v. When it happened I could not open doors or unplug. AAA jumped battery so I could open door. Didn't risk driving it, had it towed to SC. Fortunately there is a Frunk release in the lower apron.

"Customer vehicle is shutdown in Garage. Customer states they plugged in the
vehicle to charge on 12/11/2018 at 7:30 AM and the next day on 12/11/2018 at
1:30 PM found the vehicle would not turn on and could not unplug the vehicle.
Technician checked logs and found fault when customer plugged in their
vehicle to charge over night. Technician determined the 12v battery needs to
be replaced and replaced it as a one time goodwill"

muralikolli | 21. august 2019

Mine is 12 months old, driven 15k miles and just had the sign pop up about the 12V battery. Just dropped it off at teh Service Center to get it fixed.

muralikolli | 21. august 2019

Mine is 12 months old, driven 15k miles and just had the sign pop up about the 12V battery. Just dropped it off at teh Service Center to get it fixed.

COrich | 22. august 2019

Although mine is at the body shop right now and I can't check things, I've had it for 2.5 years and put on about 60K miles so far. Still on the original 12v battery.

darlow | 01. september 2019

With all of the advances Tesla has made in battery technology, I can't believe they install a 12 volt battery in these cars that needs to be replaced after 2-3 years in a Model X. Service tech told me the batteries in the Model S only last 1 to 1 1/2 years. Just before I got to 50K miles, I spent another $4800 for the extended warranty. Only to learn the extended warranty DOES NOT COVER the 12 volt battery (they told me it was a consumable like the brake pads). I love my Model X, I just don't understand the 12 volt battery issue...

crannxx13 | 02. september 2019

It might be because of overload or else this car is op.

TeslaTap.com | 02. september 2019

@darlow - The 12v batteries on all cars have a finite lifetime. Some of BMW's models have a 12v battery that needs to be replaced every year. It's all tradeoffs. You could put a larger battery that lasts longer, but it takes up more space, costs more (i.e. increasing car purchase price) and the extra weight reduces range slightly.

What may seem odd, the more you drive the longer the 12v battery lasts in the Tesla. If you drive 5,000 miles a year, 18 months maybe all the life you're get. Drive 15,000 miles a year, and it may last 4 years. There are other factors, such as heat and cold also affect the 12v battery life, as it is not thermally protected like the main battery.

jppoetsol | 02. september 2019

My current car is a 3 series BMW that has only averaged 3 to 4k miles per year. The first battery died after 1.5 years and was replaced under warranty. At the time, BMW recommended I buy a Battery Tender Plus, and top the 12V up every month or so, which I have done. Six years later and I have not had to replace the battery since.

I don't have my Model X yet. How hard is it to access the 12V battery, if you want to hook up something like the Battery Tender to it?

X Red 5 | 02. september 2019

I got the 12 volt battery warning on Friday 8/23, made first available mobile appointment for 8/27, Monday 8/26 my appointment was canceled due to a 12v back order but assured by the tech via text I would be fine until the new battery is here. Only 2 1/2 years old with only 19,600 miles.

Well, started to smell a sewer smell Thursday night in my rooms above the garage thinking we had a broken sewer pipe. My husband tried to find the leak Friday but the smell was not strong yet. We drove the car to our favorite breakfast place on Balboa Island where after I parked the sulfur smell was so strong we thought it was coming from the bay. We thought bay gas got trapped into our garage because this does happen on warm days. The smell went away until the next morning but followed us to the vet that also could come from the bay or back bay.

Needless to say figured out it was coming from my MX. Have not been able to get in-touch with anyone in service during this holiday. Saturday the smell got so strong I had to move the car to the street where it still sits until tomorrow. Thank you for the post it helped ease my mind that it will not burst into flames. Read online that this happens with 12 volt batteries when they are over charged getting hot the battery water acid expands. The smell is actually toxic gas so glad got it out of my garage.

I checked for the smell this afternoon, it is gone, my app will not connect and not responding to key. It’s dead Jim! Guess going to use roadside service tomorrow morning.

I love and am very attached to my MX and hate it is on the street where my 2001 Lexus has got a lot of damage after just two years on the street after kicked out of the garage for my MX.

JAnnen | 03. september 2019

jppoetsol: I use knock-off Battery Tenders on my lawn tractor, cars and trucks, but NOT on my MX. Much better is to set the L1 or Level 2 charge to 5 Amps, or just high enough current to get the charge I desire. The low current keeps the high Voltage buss is energized. The MX has it own Battery Tender like protection when the high Voltage buss is energized. "A plugged in Tesla is a happy Tesla."

Now I'm going to go plug my MX back in. I forgot. Thanks for reminding me.

TeslaTap.com | 03. september 2019

@X Red 5 - Well that sucks! Ok, it sounds like your 12v battery had an unusual failure. Perhaps a shorted cell or a crack. Not at all like the normal 12v degradation that is detected and you have 3-4 weeks before failure. Normally there is no smell either when the 12v battery ends its life.

jppoetsol | 03. september 2019

@JAnnen That is a better solution, but it then makes me wonder why people are having this issue? Do some people not leave their vehicles plugged in @ home?

JAnnen | 03. september 2019

jppoetsol: Most people charge at their highest rate to a curtain SOC, maybe 80%. Then the charging stops and the high Voltage buss shuts down to save energy. When the system detects when the 12V battery is low, it boots the HV buss,which means cycling the 12V battery. Keeping the HV buss energized prevents cycling the 12V battery. Less cycling translates into a longer life which is Battery Tender trick.

Disclaimer: My 12V battery was replaced after 2.5 year and 40,000 miles, but I think that's because I don't usually plug in when the traction battery is above ~65% SOC. I'm now thinking of plugging in more frequently with the low 5A current, because my next 12V battery will be at my expense.

jppoetsol | 03. september 2019

@JAnnen, got it. I will keep that in mind.

crannxx13 | 03. september 2019

jppoetsol: Most people charge at their highest rate to a curtain SOC, maybe 80%. Then the charging stops and the high Voltage buss shuts down to save energy. When the system detects when the 12V battery is low, it boots the HV buss,which means cycling the 12V battery. Keeping the HV buss energized prevents cycling the 12V battery. Less cycling translates into a longer life which is Battery Tender trick. https://reversephonelookup.onl/ https://curated.onl/nba-reddit/

i agree!!

ecsiii | 20. desember 2019

Is there a way to contact Tesla support by phone? I just got a 12v battery needs replacement notice on my
Model S85D? I am 200+ miles from a service center and I don't want to undertake the trip unless I know I can get there.

Julieanne916 | 20. desember 2019

Is there a way to contact Tesla support by phone? I have a 12v battery needs replacement notice on my Tesla X for the last week am leaving for road trip through snow territory with kids tomorrow. I have been trying to get in to get it replaced but no appointments call backs or emails back and I really need info and assistance!

Triggerplz | 20. desember 2019

@ecsiii Once I got the battery needs replacing notice I drove a week before the ranger came to my house and replaced it, the Tesla support number is 8777983752 press 2 then 3. Good Luck

Singer.andy | 21. desember 2019

Got warning today, this will be second 12 volt battery replacement in 3 years and 37K

raschultz | 28. desember 2019

Had my model 3 less than a week, 80 miles and got this message. Was out to dinner and when I tried to leave, the system wouldn't get out of park. Called Tesla and they helped reset system. Got home and they called telling me there is a system problem and take it to the service center immediately. Dropping off this AM. Great first week with the car. 80 miles and already has failed. :-(

dmanincali | 07. januar 2020

Just got this warning on our MX. It's just over 2.5 years old and at 22,644 miles. Mobile tech is coming out on Thurs to replace it.

goku2100 | 12. februar 2020

Charging at 5a isn't really all that useful for maintaining the 12v battery. I know this because I did it and I still got the dreaded 12v battery failure notification. I've got a trickle charger on the 12v battery right now in addition to the main charging cable so we will see if that makes the 12v battery failure notification go away.

eddie.k.lau | 21. februar 2020

December 2018 Model X, the 12V battery requires Service message came up on Tuesday, the service tech is here now on Friday, but after replacing another message came up about low battery on the new 12V one. Tech and service are now trying to figure out their next move.

eddie.k.lau | 21. februar 2020

Turns out when you replace the batter, sometimes a fuse blows. All is good now, but I had to pay a bit over $200

Passion2Fly | 21. februar 2020

12V battery has just been replaced after 4 years and 35k miles... not bad!

Passion2Fly | 21. februar 2020

~$250

ericdirect | 07. mars 2020

This seems off. On my other european make cars the batteries last easily 8 years (10 for Mercedes). Should we trickle charge them too if you leave your MX for extended periods of time?

TeslaTap.com | 10. mars 2020

@ericdirect - As long as you plug in, even a low-power outlet, it is better for the car. Trickle charging is then unnecessary.

If you're leaving the car for an extended time, you can turn off the car, in Controls. This reduces the number of 12v charging cycles and will extend the 12v battery life. You will not be able to communicate with the car remotely.

Longer battery life was more common in older cars without much electronics. Most higher-end new cars are lucky to make it to the 4-year mark. In some higher-end BMWs, the 12v battery only lasts a year, due to poor design. They no longer use that design.

luke.gardiner | 30. mars 2020

Just picked mine up today brand new, first thing it said was the 12v battery issue error message.