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12v battery died 250 miles from SC making me pay for 150 mile towing

Discussion in 'Model S' started by Lhagin, Dec 20, 2015.

  1. thimel

    thimel Member

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    My model S gave me a warning that the battery needed replacing. In fact, a Tesla ranger is coming out tomorrow to put in a new battery. My car is only 9 months old. My understanding from other threads on this forum is the battery dies early because of the large vampire drain when the car is not on. This repeatedly runs down the battery until the car turns on the dc to dc converter to recharge it from the main pack. This repeated cycling kills the battery.
     
  2. Tedkidd

    Tedkidd Member

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    I think they're gonna need to ramp up deployment on service centers. Dissatisfaction with service burden subsequent to change in the ranger program seems to be creating growing dissatisfaction, and 300 miles from mid-tier cities isn't gonna work for model 3.

    My Smart has to go to Buffalo. They're good about towing to and from (at least under warranty) but I'm not sure I'd do it again - and that's 65 miles.

    All of upper NY is a Tesla service desert.
     
  3. Cyclone

    Cyclone Cyclonic Member ((.oO))

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    Just a note thimel that this happens while the car is in use too (I think). Basically, the battery deep cycles often. I believe I've read 2-4 times per day? Maybe it does shallower cycles when the car is in use, but it seems like the car uses the 12v in isolation than charges it up via the DC-DC as needed.
     
  4. Spidy

    Spidy Active Member

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    Doesn't Supercharging need a lof of cooling and the fans are powered by the 12V battery?
     
  5. Cyclone

    Cyclone Cyclonic Member ((.oO))

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    I don't know about the fans, but the compressor has a dedicated power connection from the traction battery and the traction battery itself has an "evacuation system" for expelling heat. So I imagine that some options exist for Supercharging the traction battery on a car with basic power going still.
     
  6. tstafford

    tstafford Supporting Member

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    I'm probably missing something - but is a battery replacement something that needs to be done by the SC? Can't any place like Firestone do it?
     
  7. Chrisizzle

    Chrisizzle Member

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    I was covered for an 800 mile tow.

    I had a 12v battery failure while working in Green Bay, WI after driving from Toronto, Canada (900 miles with various indirect stopovers).

    It was after 11pm and Tesla service offered a hotel and rental car in the morning. That wasn't going to work. I needed to be somewhere by 5am and immediately depart for another 150 miles north when that wrapped.

    Option two was trying the airport in case those car agencies were open 24 hours. They were not.

    The Tesla guy left me in suspense when he said "I am working on something. Let me get back to you". He returned with this incredible solution:
    - Load a demo Model S from the Chicago showroom onto a flatbed truck at midnight.
    - Drive that to my hotel in Greenbay by 4am (200 miles)
    - Take my car to Chicago for repairs (200 miles) while I used the demo for 3-days.
    - Offered to swap back when I was ready (the same 400 mile round trip).

    I had to drive through Chicago on my way to Toronto and returned the demo myself. However, they were ready and willing to do the full 800 miles of towing if required.

    Needless to say, my client and I were blown away by Tesla's level of service. Now, I tell this story to anyone who will listen.
     
  8. Lhagin

    Lhagin New Member

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    Dhanson865 thank you for that great advice. I'll be purchasing the devices today. Now I just need to know how to access an charge the 12 V battery for future reference. Any goo YouTube videos that you would recommend? Also I am hearing a definite "clunk" when I let off the accelerator. In reading the forums I think it's either a bushing or my battery. Can't wait to hear what they have to say to that.
     
  9. msnow

    msnow Active Member

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    ^^ amazing customer service @Chrisizzle. I assume you are on the basic service plan and not on Ranger service.
     
  10. BertL

    BertL Active Member

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    Sorry you had this problem. ...but really, everyone IMHO should read warranty and service terms in advance of a major purchase -- even though I suspect most probably don't. While researching my own MS over the summer, I noted places where the Tesla terms are both more restrictive, as well as "more nebulous" (leaving interpretation more open perhaps on both sides) compared to Lexus, MBZ and BMW that I've also owned in recent years.

    FWIW, when I bought my first Acura the year dealerships opened here in the US back-in-the-day, there were not very many Acura dealerships anywhere and I was putting high mileage on my rides for business every day between SoCal and AZ with lots of open desert in some stretches... Before buying, I asked my sales person what I'd do if I were stuck in the middle of nowhere, and their answer was any Honda dealer would help in a pinch; It was the same when I purchased my first Lexus 20 years ago and their references to Toyota dealers. In fact, many Lexus owners to-this-day use Toyota for non-warranty service as it's generally a lot cheaper alternative. As has been said, we don't have those sort of options with Tesla -- they don't have an established parent company with a huge dealer network to back them up; they are still building out their SC infrastructure; and Tesla does not provide service information to other shops or their own customers to perform work. It's one of the perhaps "not-as-good as some other luxury brands" items when considering the Tesla brand these days, but for most that are not in the middle-of-nowhere and closer to metropolitan areas, Tesla Service appears pretty good most of the time, and goes well beyond the call in others.

    On one of your other posts: I do have a AAA Plus Membership (100 mile free tows compared to Classic with 50) that I could use as a towing alternative to Tesla if need be. Premier is another option, but to me, it's like insurance, and the times I'm not within 100 miles of a Tesla SC are pretty rare so I take that chance vs paying the money to have up to 200 miles for a single tow each year, when even with Premier if one reads AAA terms closely, it drops to 100 free miles on subsequent tows in the same year...​

    If I were you, I'd very politely and in a business-like manner, either talk to the local Service Center Manager asking for an exception on the towing policy to recoup your costs, or write Tesla North America Customer Service with the same request. Good luck.
     
  11. Spyder14

    Spyder14 Member

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    Yes--several years ago my 2007 Audi A6 had a coil pack fail & I called the dealer & they called the flatbed tow to pick it up. All under warranty.
     
  12. murphyS85

    murphyS85 Member

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    There are jumper terminals for the 12 volt battery behind the nose cone.
     
  13. msnow

    msnow Active Member

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    My question to the OP is if it was just a question of needing a jump why didn't Tesla just try that before the long costly tow?
     
  14. BertL

    BertL Active Member

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    Behind the nose cone, upper right towards the top are the connection points. Check your Owner's Manual for info how to remove the nose cone and more info.
     
  15. Saghost

    Saghost Well-Known Member

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    Yes and no. Everything you said is true, but it isn't the complete picture. There's a DC-DC converter which takes 400V power from the big battery (or the Supercharger itself, while supercharging,) and uses it to charge the 12V battery. In principle, all power ultimately comes from there.

    However, I'm not sure what the capacity of the DC-DC converter on the Model S is - it is possible that the loads on the 12V sometimes exceed the DC-DC capacity, which would mean taking power from the 12V battery to make up the excess during those high load periods.
     
  16. dsm363

    dsm363 Roadster + Sig Model S

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    This must be a difficult issue for them to solve if it is still happening without some major redesign.
     
  17. MsElectric

    MsElectric Active Member

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    I think it is more important to let the owner know via a message as the owner has a vested interested in not being in a situation where they are stranded...

    Is there some way in the settings menu to know the health of the 12V battery and voltage? Seems like this is a useful thing to know, especially if you are about to go out of town or a trip. At the least can you call Tesla before going on a long trip so they can remotely gauge the health of the 12V battery and let you know?

    I wish they'd figure out a more robust implementation of the 12V system. Could they not have a backup Lithium-Ion battery that can be charged via the main battery pack for an emergency so that the car can be started a few times in such a way so you can at the least drive out to service center? Seems other than the 12V battery, the rest of the car was perfectly fine.

    Can the 12V battery be replaced on the field by anyone or does it require disassembly of car components to reach the 12V battery?

    - - - Updated - - -

    Wow. That's outstanding service. No other car manufacturer would have done this. It is astoundingly wonderful their employees care so much and have the authority to get things done for a car customer well after business hours. Obviously they messaged the manager of the Chicago Showroom to coordinate this.

    I still think they need to come up with a better solution to prevent a car from being stranded over a 12V battery or at the least come up with a foolproof way to warm an owner well before the 12V battery is completely gone.
     
  18. dhanson865

    dhanson865 Active Member

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    You can either use the front nosecone 12v connectors seen in Tesla Motors Model S -- Dead 12v Battery -- What to do to get back up and running (Roadside Service) - YouTube

    or wire an always hot 12v "cigarette lighter" style connector so you can use the CTEK (56-263) Comfort Connect Cig Plug.

    If either of those seem daunting you might want to see if the service center will make a 12v socket always hot (for free or for some small charge). If they won't do it go to a highly rated car stereo installer and get them to do it.

    With a comfort connect plug you'd just roll the window down and plug into the cigarette lighter socket while the car is turned off and then press the buttons on the CTEK to start a charge session.

    In my Prius I do that with an always on port, in my Leaf I open the hood and use the alligator style clips directly on the battery. On the Tesla they hide it further in so an always on plug in the dash will be the most convenient for repeated use.
     
  19. TexasEV

    TexasEV Well-Known Member

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    No. It's not a normal car battery and it's not easily accessible. When my 12V was failing last year I didn't know about it until I got a call from my service center saying the car logs showed it needed to be replaced, and they came to my office, picked up the car, replaced the battery, and returned the car to me.
     
  20. arg

    arg Supporting Member

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    That's not a valid comparison. In fact, the situation when driving is much like an ICE - the Model S DC/DC converter supplies the 12V loads and charges the battery, just like the alternator in an ICE. In neither case is the battery disconnected once the DC/DC or alternator gets going.

    The major differences between Model S and ICEs are the amount of power used while the car is 'switched off' (higher on the Model S), and the size of the battery (smaller). The combination means that the battery gets cycled while the car is parked, with the DC/DC powered up occasionally to recharge it.

    You might say "why doesn't the DC/DC run all the time to save cycling the battery", but I imagine the answer is that the power taken to run the contactors, main pack battery management etc. would be just too large.

    My theory is that whoever specified the 12V subsystem on Model S expected the software guys to do much better on power save in the various on-board computer systems, but with the rush to get the car out of the door that was never achieved, leaving the power drain much higher than it should/could be, and making what was originally a reasonable choice of 12V battery turn out inadequate.
    It's always much harder to put power management into a system after it's been built rather than doing it from the beginning, so it's not clear whether they have simply never had the development time to get it right, or if some architectural mistake was made early on that makes it impossible to fix now.

    It's also not clear to what extent the 12V system is "still broken". Every time we hear of 12V problems, people cry "why is it still not fixed", when many times it's not the 12V battery that was the root of the problem - almost any problem in the high voltage system will cause that to shut down, and then within a few hours the 12V will go flat. So the low 12V warning may be the first thing the driver sees when it wasn't a 12V fault at all.

    Undoubtedly the 12V would last longer if it was cycled less, but the current life is probably tolerable if not as good as we'd like.
     

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