Welcome to Tesla Motors Club
Discuss Tesla's Model S, Model 3, Model X, Model Y, Cybertruck, Roadster and More.
Register

Preventative 12V battery replacement before road trip?

This site may earn commission on affiliate links.
My 3 is coming up on 2 years and 23,000 miles, and I'll be taking it on a road trip halfway across the US in a couple months.

My concern is the 12V battery dying - it seems the car is supposed to give you plenty of warning that it needs to be replaced, but that's not always the case, and I don't want to be stranded in the middle of nowhere. Would it be worth getting the 12V replaced (paying for it out of pocket of course) before I leave? Does anyone know what it costs for mobile service to replace it? It seems like it might be some piece of mind, especially if it's going to have to be replaced soon anyways as 2-3 years seems to be the typical lifespan from what I've read.
 
My 3 is coming up on 2 years and 23,000 miles, and I'll be taking it on a road trip halfway across the US in a couple months.

My concern is the 12V battery dying - it seems the car is supposed to give you plenty of warning that it needs to be replaced, but that's not always the case, and I don't want to be stranded in the middle of nowhere. Would it be worth getting the 12V replaced (paying for it out of pocket of course) before I leave? Does anyone know what it costs for mobile service to replace it? It seems like it might be some piece of mind, especially if it's going to have to be replaced soon anyways as 2-3 years seems to be the typical lifespan from what I've read.

I'm over 2 years now and 27k miles, and the 12V battery is holding strong. I'd say that's a waste of capital at this point... no need to proactively replace it anytime soon. Just got back from a road trip to Florida and it was fine. To be honest, road trips like that are almost no stress on the 12V battery at all...
 
My 3 is coming up on 2 years and 23,000 miles, and I'll be taking it on a road trip halfway across the US in a couple months.

My concern is the 12V battery dying - it seems the car is supposed to give you plenty of warning that it needs to be replaced, but that's not always the case, and I don't want to be stranded in the middle of nowhere. Would it be worth getting the 12V replaced (paying for it out of pocket of course) before I leave? Does anyone know what it costs for mobile service to replace it? It seems like it might be some piece of mind, especially if it's going to have to be replaced soon anyways as 2-3 years seems to be the typical lifespan from what I've read.
Better safe than sorry. The battery itself is cheap, $85. Labor for mobile tech, I don't know, but I think peace of mind is worth it. Getting stranded is far more costly in time wasted, and a trip ruined.
 
My 3 is coming up on 2 years and 23,000 miles, and I'll be taking it on a road trip halfway across the US in a couple months.

My concern is the 12V battery dying - it seems the car is supposed to give you plenty of warning that it needs to be replaced, but that's not always the case, and I don't want to be stranded in the middle of nowhere. Would it be worth getting the 12V replaced (paying for it out of pocket of course) before I leave? Does anyone know what it costs for mobile service to replace it? It seems like it might be some piece of mind, especially if it's going to have to be replaced soon anyways as 2-3 years seems to be the typical lifespan from what I've read.

Op, I think in your specific case I would replace it (with "your specific case" being "I am about to go on a road trip across 1/2 of the US"). Since its relatively cheap for the part (no idea what the cost is to replace), if I was in your shoes I would just do it.

With that being said, I am over 2 years and 26k miles on my own model 3P and it seems fine, no symptoms of 12V failure, but I am also not measuring it, etc. I have been contemplating replacing it proactively as well, but since tesla just opened up a service center in my city, vs the one I used to go to that was close to 40 miles away, I decided I would wait for it to fail so it would be free, if it does happen.

Anyway, the fact that you are thinking about it, OP, means that, IF you choose not to replace it proactively, and IF something happens, you will be "super" mad at yourself for not doing it, likely mad enough to impact the rest of your trip. I know I am projecting here, lol. If you didnt think about it ahead of time and it happened, /shrug.... but now that you have, you almost have to do it to not let it impact your trip if it does fail during it.
 
2019 TM3P: 22months, 30-31k miles. Just got the 12V battery degradation message so I have mobile service coming Monday as I’m under the impression it’s covered by the warranty. Im in hot south Texas.

even with that being said, I don’t think it’s necessary for you to replace…but if it helps you sleep better, it won’t be that expensive.

Now, people saying batteries die in high heat. Both of my BMW’s batteries lasted 7-8yrs. (Admittedly they are tractor batteries)
 
My 3 is coming up on 2 years and 23,000 miles, and I'll be taking it on a road trip halfway across the US in a couple months.

My concern is the 12V battery dying - it seems the car is supposed to give you plenty of warning that it needs to be replaced, but that's not always the case, and I don't want to be stranded in the middle of nowhere. Would it be worth getting the 12V replaced (paying for it out of pocket of course) before I leave? Does anyone know what it costs for mobile service to replace it? It seems like it might be some piece of mind, especially if it's going to have to be replaced soon anyways as 2-3 years seems to be the typical lifespan from what I've read.
I am at 38 months and 57,000 miles and the 12v seems just fine in my car.
 
  • Like
Reactions: SunCharged
I replaced ours at 2 years due to climate. Rarely do 12V batteries last 2 years in high heat. 1 year in on our ohmuu and it's still strong.
Hmmm, then mine must be rare. It gets REALLY hot up here in the summer and really cold in the winter. Mine hasn't been replaced in 4 years. Still seems strong according to the service center (which is very close to me anyway). When I go on my next long trip I will proactively replace it in advance.
 
  • Informative
Reactions: FlyF4
there's a degradation message?.....okay good, I didn't realize that.....all I've read before is it just dies.
This is the message I got on Friday.

Tesla confirmed my appt for tomorrow to replace the battery at zero cost to me.
 

Attachments

  • 89C5743B-502D-4F9A-B0DD-C2E6B30E6624.jpeg
    89C5743B-502D-4F9A-B0DD-C2E6B30E6624.jpeg
    1,004.9 KB · Views: 164
Worriers gotta worry. Did you replace your 12 v battery on your ice vehicle every time you went on a trip?

I've had 4 Teslas since 2012. First two had over 100K miles on them, roughly 4 years old, NEVER replaced any battery, 12v or otherwise. What ruins a lead acid battery is letting it drop to a low state of charge, and that never happens with a Tesla.

Since you can find a battery at virtually any service station, why not quit worrying and buy a battery when you need it. I know, novel idea, but the battery is much better taken care of in a Tesla than in a gas burner.

Believe me, Tesla takes care of its batteries. Go on your trip, and buy your battery when you need it. It doesn't just die overnight. You'll have plenty of warning. Likely that will happen years down the road.
 
Seemed like there was a rash of Model 3 batteries dying after two years in 2020. Could have been a bad batch. Maybe Tesla started treating them better. Maybe that's just going to be normal.

Our 9/2018 Model 3 12V battery went bad without prior warning. Lots of warnings and a pump or motor in the frunk that wouldn't stop running. Simple resets didn't fix anything, but after a few days my wife decided to try driving it to the Service Center. That went OK and the SC replaced the battery in less than an hour. You don't want that on a road trip.

This is not just any battery. You may not easily find an exact replacement at a car parts store. However, in a pinch I'd use whatever would fit, as a short term solution.

If the money to replace the battery now is worth it to you to avoid the risk of a trip interruption, go ahead and replace it. Our Model X did give me an advanced warning. Since it is our road trip car, I replaced it with an ohmmu lithium.
 
  • Like
Reactions: jjrandorin
They do fail. I replaced mine on my S proactively. I drive many more miles than most people here. Often in the middle of nowhere. Far from Supercharger world and so called battery stores everywhere. When it doesn't work, it just doesn't.

I would say that if you do your research here you will find many a person who had it fail with no warning. Sure those are the people that tell the story. Some issues that can cause other issues as @animorph mentioned is the battery. In fact the charge port that I just had replaced. Before replacement they checked the battery. Slow engagement is also a symptom of dying 12v.

That has to be in my book of something I would gladly pay for to rule out early on. That is why I replaced mine on the S at around I want to say 90k in miles. I also did the 3 at 80k.

Key West Dec 24th you are not getting a battery at your local auto parts store nor the 25th or the 26th. I love it when people say throw caution to the wind when they aren't the ones on the side of the road. I did that trip just recently with a full car and a family. So it came to mind. If something like that occured with a dead 12v. Three people would be giving me a strange look. Good trip looking back.
 
I think it depends on what your trip route is and what you will be doing. If you are going to be in remote sections in the western US where your be a hour plus from a battery and/or you plan on camping in the car and using the 12 volt battery to run the climate control fan I might consider changing it.

I took a 4200 mile ride trip which included Wyoming, Montana, and North Dakota but we were camping so I didn’t replace mine. It wasn’t extremely cold during my trip either.

$85 is cheap peace of mind especially since if you plan to keep the car more than 5 years you’ll eventually replace the battery.

Have a safe trip and enjoy it, too.
 
  • Like
Reactions: AlanSubie4Life
I think I may have been hearing that the Model 3 was having a bit more trouble with the 12V batteries not giving enough warnings of going bad. I have a 2014 Model S, and it has the bad 12V warning on it right now (came on about 4 days ago or so), and I have an appointment to get it replaced this week. They usually do have a few weeks of warning before they die. And as a data point on the time span, this is my second replacement of this battery in 7+ years, so they can sometimes last pretty decently.
 
  • Helpful
Reactions: Silicon Desert
I proactively replaced my standard battery with an Ohmmu lithium battery. Much lighter. 10 min. install and they have a video outlining the steps. If you have any issues Ohmmu is will work hard to replace or correct. I've used it summer and winter. I kept my original battery as a backup.
 
2019 TM3P: 22months, 30-31k miles. Just got the 12V battery degradation message so I have mobile service coming Monday as I’m under the impression it’s covered by the warranty. Im in hot south Texas.

even with that being said, I don’t think it’s necessary for you to replace…but if it helps you sleep better, it won’t be that expensive.

Now, people saying batteries die in high heat. Both of my BMW’s batteries lasted 7-8yrs. (Admittedly they are tractor batteries)
My experience with a BMW and an Audi was that both OE AGM battery lasted 7-8 years. I'm really impressed. (I live in a mostly moderate climate.)