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12V battery replacement, whos had to do one?

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Just curious, who all has had a 12V failure on your MX? Did you have any other electronics installed? Dashcam?

Ive got a blackvue DR900 installed with the trailer hitch method.

Just curious how common of a problem is this
 
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Welp good news folks, tesla roadside was able to come over and replace the 12V today.

the repair was quick maybe 20 mins.

So interesting factoid I learned today. There’s this hose that That connects to the 12V battery to exhaust fumes to a specific vent in the FRUNK.

From the hose itself I guess my old battery really gave out.
 
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Every lead acid battery I have ever owned in any application has failed eventually. The record is held by a small one that started a 5 kW generator. It lasted 10 years and that's twice what the better ones usually do. Most good ones seem to go about 5 yrs but I do have some marine ones in my boat that are on their 6th season. I'm nervous about them.

Assuming that Tesla is using a good grade of battery here they should last about 5 years. After that we can all expect that they are going to have to be replaced reasonably soon. If I keep this car that long I'll probably consider changing out that battery just to avoid potential unpleasant surprise on the road just as I'll probably swap out those marine batteries to prevent an unpleasant surprise in the middle of the lake..
 
Every lead acid battery I have ever owned in any application has failed eventually. The record is held by a small one that started a 5 kW generator. It lasted 10 years and that's twice what the better ones usually do. Most good ones seem to go about 5 yrs but I do have some marine ones in my boat that are on their 6th season. I'm nervous about them.

Assuming that Tesla is using a good grade of battery here they should last about 5 years. After that we can all expect that they are going to have to be replaced reasonably soon. If I keep this car that long I'll probably consider changing out that battery just to avoid potential unpleasant surprise on the road just as I'll probably swap out those marine batteries to prevent an unpleasant surprise in the middle of the lake..
I might be misunderstanding your post, but I wonder if you know that not all Teslas use the same type of battery than in an ICE car? And they are regularly discharged and charged deeper. Thus, not really a comparison age wise.
 
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I've related my experience with lead acid batteries of various architecture from car to marine to burglar alarm to UPS to generator to mo. The come in various grades. You can go to your auto supply store and pay less for a 3 year battery and more for a 5 year battery. The best tend to go full bore out to 5 yrs and then die pretty suddenly but as noted I have seen them go more than 5 yrs and in one case 10 and this wasn't a high grade battery. As these events are random in nature the best we can give you is a statistic like MTTF (mean time to failure).
 
My MX just flashed the 12v battery needs replacing. I called Tesla and they have advised me that the battery for the MX is on back order and may be 7-10 days before it can be replaced. My whole dash has now lit up with warnings. ABS not functioning properly, stability not operating properly, autopilot not currently functioning. Tesla has advised to keep the car in my garage until they can send a mobile service to replace the 12v. They will then look into all of the other issues the MX is having. I was told to rent a car for the duration since a loaner car is not available at this time. This is very frustrating since I have had the MX for just under 1 year. This is a major investment for me and I feel like I’ve just been punched in the stomach wondering if I made a bad decision. Has anyone else experienced something like this or is this unusual?
 
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My MX just flashed the 12v battery needs replacing. I called Tesla and they have advised me that the battery for the MX is on back order and may be 7-10 days before it can be replaced. My whole dash has now lit up with warnings. ABS not functioning properly, stability not operating properly, autopilot not currently functioning. Tesla has advised to keep the car in my garage until they can send a mobile service to replace the 12v. They will then look into all of the other issues the MX is having. I was told to rent a car for the duration since a loaner car is not available at this time. This is very frustrating since I have had the MX for just under 1 year. This is a major investment for me and I feel like I’ve just been punched in the stomach wondering if I made a bad decision. Has anyone else experienced something like this or is this unusual?

My MX has been sitting at the service center for a week now waiting for a battery. I’m told there is a nation wide shortage. Fortunately I was able to get a loaner after the first few days.

This will be my third 12v battery in 2.7 years. My first failed after only 4 months.
 
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View attachment 444495 Welp good news folks, tesla roadside was able to come over and replace the 12V today.

the repair was quick maybe 20 mins.

So interesting factoid I learned today. There’s this hose that That connects to the 12V battery to exhaust fumes to a specific vent in the FRUNK.

From the hose itself I guess my old battery really gave out.

Where does that hose connect? I see it drains out just to the under side of the car, but I didn't see where the other end connected.
 
The other end would connect to a vent port on the battery.

Question: does anyone know anything about the Ohmmu lithium replacement for the 12V battery? Other than that it is expensive. I already know that.

Observation: If you are wondering where some of phantom drain goes put your hand on top of the fuse/relay box cover. It is, in my car, noticeably warm.
 
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My "12V battery requires service" alert came on this morning. (Battery lasted 3 years, 4 months) Is there a rule of thumb on how much time has once this comes on to replace? (Already have a mobile appt in a week but just curious)
I don't want to get my tech in trouble, but during the battery replacement he admitted to me that the threshold for "battery requires service" is way too conservative. He said in most cases the battery would have lasted much longer. But when the "battery requires service" alert goes up you can't do various things (no software updates, summon, etc) so you are kind of forced to do the replacement.
 
View attachment 444495 Welp good news folks, tesla roadside was able to come over and replace the 12V today.

the repair was quick maybe 20 mins.

So interesting factoid I learned today. There’s this hose that That connects to the 12V battery to exhaust fumes to a specific vent in the FRUNK.

From the hose itself I guess my old battery really gave out.
Thanks again! I re-opened the frunk and reconnected that hose you mentioned! Very easy once you know where to look.