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Dead Battery

Dead Battery

I just found out that they will not send mobile service for just a dead 12 volt battery. They said they are not available for a day or two and won't give me a time when they will come. I have been handling this for 4 days now. The car will now be towed over 100 miles. I will not have it for I have no idea how long, no loaner, and will have to travel to get it. I was also hung up by roadside service when I asked a few more questions but I was very professional. I have an individual which on the fence with a Model 3 and I am pretty sure this will convince to not buy.

andy.connor.e | 17. mars 2020

Why does every bad experience have some cliché statement about the experience making them want to sell, or stopping someone else from wanting to buy. Do people think that car buying results in a 0% chance of a bad experience?

Magic 8 Ball | 17. mars 2020

Uh, worldwide crisis ring a bell? Been to a market lately?

TeslaTap.com | 17. mars 2020

A dead battery is usually an indication of something more serious, perhaps the DC-DC inverter has died. I can see why they need the car at the shop to test and repair.

I've never heard of a shop for any make car that can tell you exactly how long a repair will take on something they have not evaluated and diagnosed. Seems you're expecting a lot more from Tesla than any other manufacturer.

Agree roadside should have helped you out more with your questions if on topic, but I expect once they understood the car has to go to service, they may not know much more. They are mostly there to dispatch a tow truck. It's unfortunate you're so far away from a service center for this problem. It is a concern for those that live in a state that doesn't allow service due to dealer laws or live far away from service.

hokiegir1 | 17. mars 2020

I was almost positive this was the followup to this other thread, but it might not be:
https://forums.tesla.com/forum/forums/battery-died-while-vacation

bjrosen | 17. mars 2020

I have to agree with TeslaTap, there must be something more serious than just a bad battery. No Model 3 is old enough to have a 12V battery die of old age, modern batteries are good for 7 or 8 years and that's in an ICE car where it has to crank a starter motor, something that it doesn't have to do in an EV.

Earl and Nagin ... | 17. mars 2020

@bjrosen,
I agree that there should not have been any problems with Model 3's yet. Ours is about as old as any at over 2 years old and our battery seems to be doing well.
Your 7 or 8 year estimate may be a bit optimistic though. I generally have gotten about 4 years out of our Leaf 12V battery and 1999 RAV4EVs generally only got a couple of years from them.
There's something about the load from an EV that puts a lot of wear on a Pb-A starter battery.

lbowroom | 17. mars 2020

Bj, model 3 battery is much smaller because it doesn’t have ac starter to crank. Many batteries fail in cars in 3-4 years. There have been bad batteries reported for model 3.

bjrosen | 17. mars 2020

Earl and Nagin@ My Volt is almost four and it's battery is fine. My 7 or 8 year number is from my last ICE car, a Chrysler 300C Hemi, the original battery lasted eight years and turning over a V8 is hard work. Before that all of my cars going back to the 70s consistently got 4 years on a battery but the big thing that changed with the 300C was that the battery was in the trunk instead of under the hood. I was give to understand that by isolating the battery from the heat of the engine it's life was significantly extended. In a Tesla there is no engine to bake the battery which is the basis for my assumption that the life expectancy should be at least as good as the 300Cs. You may be right that other aspects of the load are more stressful for a lead acid battery but I can't imagine what that is.

WW_spb | 17. mars 2020

Who cares about dead battery when we don't have Toilet paper. God damn

don.lind | 17. mars 2020

I just wanted frozen peas at Trader Joe's the other day.
The WHOLE freezer thing (like 40 feet long) was devoid of food - except I think there were 2 bags of frozen corn.

TeslaTap.com | 17. mars 2020

@WW_spb +1 :)

@bjrosen - Use case in an EV vs ICE is quite different. The battery in an ICE is used for starting the engine, and once started, does nothing as the alternator powers everything. This battery is rarely deep discharged and a Lead-acid battery works well in this application. Using a larger battery tends to make it last longer. In various ICE cars, I usually got 3-5 years out of a battery. I can see some cars getting more. I heard one BMW ICE model a few years back, it's battery could only last 1 year in an attempt to get more MPG.

In an EV the 12v battery is used all the time, stopped and driving. As it gets low, it is charged up from the main battery, going from low to full 3-5 times a day. This is a deep discharge AGM battery. I'd say on average, it lasts about 4 years. I very much doubt you can get more than 5 years out of it, but who knows?

Bighorn | 17. mars 2020

I think mine is over 5 years by now.

TeslaTap.com | 17. mars 2020

@BH - On a Model 3 - now that's impressive :)

WW_spb | 17. mars 2020

By the way I was sarcastic

bjrosen | 17. mars 2020

TeslaTap@ Do you know the reasoning for powering the electronics off of the 12V battery rather than from the traction battery? Obviously there has to be a DC to DC converter that drops the 400V down to 12V so that the lead acid battery can be charged, why not just tap off of that when the car is running?

TeslaTap.com | 17. mars 2020

The first Tesla roadsters v1 used a tap from the HV battery - not a great design choice. For one, you need to disconnect the HV in the event of a crash or electrical fault in the battery. The 12v battery is desired to retain power during such cases to power emergency blinkers, air bags, and ideally a few other items. I'm not aware of any EV today that uses the HV battery to directly power 12v via a tap. It would also tend to wear that part of the battery more than the rest too - so you don't want to replace the main battery every 4 years!

Tesla uses a DC-DC converter to charge the 12v and power accessories. It's a bit of a complex dance but works well.

gmr6415 | 17. mars 2020

@bjrosen, you obviously don't live in a climate similar to Florida. You're doing good to get 4 years out of a lead acid battery in FL. Almost all of my previous ICE cars went through batteries in 4 years or less. I also have a lot of farm equipment, that goes through batteries in about 4 years...solar powered gate with lead acid battery...3 to 4 years. Boat with trolling motor...3 to 4 years, etc.

The constant heat here kills them quick. Batteries cost more in FL, and warranties are shorter. I wait until I need to visit relatives in AL or GA and purchase my batteries there. I can save 25% to 50% and get a longer warranty.

gmr6415 | 17. mars 2020

@TeslaTap.com, "The 12v battery is desired to retain power during such cases to power emergency blinkers, air bags, and ideally a few other items. I'm not aware of any EV today that uses the HV battery to directly power 12v via a tap."

I'm not sure how Tesla is doing it but supposedly they have gotten rid of the 12v battery in the model Y, yet will have a 12v system to some extent.

Tesla Model Y To Ditch 12-Volt Battery, 95% Less Wiring Than Model 3

https://insideevs.com/news/332478/tesla-model-y-to-ditch-12-volt-battery...

I though that they weren't going to have anything 12v in the model Y until today I found that they will have a low voltage cabin heater (12v) to assist the heat pump. https://ibb.co/zW3WMsp, https://ibb.co/bdzkMpr

gmr6415 | 17. mars 2020

@TeslaTap.com, Actually the diagram in the patent application shows two 12v cabin heaters. Only time will tell whether or not they use them at all or both. https://ibb.co/HzGZkGs

Scrannel | 17. mars 2020

When I first came to California, left Vermont in a 280SL. It broke down somewhere in Kansas. Cop found me, Towed to Lawrence. Next day a local shop found the fuel pump was gone. Took a week to get the pump and I was back on the road. How things are -- electric car or not.

FISHEV | 17. mars 2020

"Why does every bad experience have some cliché statement about the experience making them want to sell, or stopping someone else from wanting to buy. Do people think that car buying results in a 0% chance of a bad experience?"

Why do non-owners, non-drivers of Tesla's such as yourself attack Tesla owners commenting on facts about their car is a better question. It's a Tesla Owners forum.

Tesla doesn't have enough dealerships...er Service Centers. Tesla knows this, has known it since it implemented Mobile Service. This sounds like exactly the kind of problem that a Tesla owner should expect Mobile Service.

Magic 8 Ball | 17. mars 2020

FISHEV is EVIL with his anti-Tesla agenda.

FISHEV has no idea what Tesla knows yet claims he does, a world class moron trying to tear down Tesla.

kaffine | 17. mars 2020

bjrosen | March 17, 2020
I have to agree with TeslaTap, there must be something more serious than just a bad battery. No Model 3 is old enough to have a 12V battery die of old age, modern batteries are good for 7 or 8 years and that's in an ICE car where it has to crank a starter motor, something that it doesn't have to do in an EV.

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I have already had to replace the 12V battery in my 3 it lasted a little over a year. I replaced it on a Friday before a long weekend Tesla couldn't get a mobile tech to me as fast as I would like so they allowed me to bring the battery in and swap it across the counter. I checked the DC-DC converter was working just the battery died.

wisniewsk | 20. mars 2020

Once I was able to get mobile service here he was able to fix the problem. An update failed in the middle of the install and completely drained the 12 Volt battery. Once he gave power to the 12 Volt battery he was able to redo the update and the car is now fine. My original problem was actually with customer service and the different stories given. The mobile technician was great and knew exactly what to do.