Ok, bear with me here, as this will be a very long post that I hope Tesla reads, and makes some changes that piss the most loyal customers off. I know I'm not alone here, not by a long shot.
I took delivery on March 15th, 2013. Since I live in the middle of nowhere, I made sure to communicate with my delivery specialist that the UMC HAS to be working when the car gets here, because without it, I would be SOL. He said that he would double and triple check the UMC, to make sure I had zero issues. As you can guess, the UMC was DOA, and my car could not charge. After playing with it to diagnose whether it was the UMC or something else, the 12V died(I put a trickle charger on it to get the car to respond again). The head of the SC at that time wanted to just trailer the car 350+ miles back to Portland(this is a just delivered brand new car mind you), and fix it, but I insisted it was the UMC. Afger a long chat on the phone discussing why it was a bad idea to haul a car over 700 miles RT for a bad UMC, he agreed to send me a different UMC. That fixed the first problem.
A month or so later came a myriad of other problems(not all at the same time) like steering rack click, front control arm rattle, window regulator problems, tire shredding issue, bad chargeport, melted UMC, and a few others. In August, the car was taken to the SC and I got a loaner. This was very acceptable as I got to try out a new P85 for a month or so. The P85 had some of it own share of problems(that's another chapter for a different time).
In the next 4-6 months some of the issues like the steering click came back, and the alignment was still way off(shreads inside of rear tires). A new issue surfaced, which was warped rotors. The car felt like a jalopy with 200+k miles on it. I jad a trip planned that would take me through Portland in August of 2014, so I scheduled a time to get a loaner and get some more of the items fixed. They went ahead and fixed them, but this time, getting the loaner was a bit of a hassle. I specifically requested that I NOT get updated to the new FW(I had 5.8 1.49.24), but got a call back saying it MUST and it WILL get upgraded, because it's a recall FW(any prior FW was recalled). After about 1+ hours on the phone arguing why I did not want ANY new FW, I gave in and that was that. The reason I didn't want new FW, was the charging current being backed off, starting with 5.8.4(there are a ton of threads here on that mess).
I forgot to mention that from delivery to about that last service visit, I had been through abot six UMC's, of which 3 melted. The melting ALWAYS happened at 40A charging , between the adapter an the UMC end, in the summertime. THIS is the real reason that the FW was dialed back, as the UMC is not engineered to handle continuous 40A charging, and instead of swapping out UMC's like mad, Tesla decided to limit the charging everyone paid for. There is no way in hell I would have bought the Model S with a puny 6kw charger on board. 10 kw is fine as that is the max out in the wild for most of America. For those of you that say what is the big deal, try spending 6 hours at an RV park dozens of times, and finding out that the time has now increased 2-3 hours, just because. I suspect one of the problems Tesla employees have is the fact that they are paid so little, they can't afford a Tesla, and have no clue what it's like to live with some of the design things that have taken a turn for the worse.
So to continue on, I headed back home from my Aug 2014 service visit, when an hour down the road, the AC got really wimpy. I was now on FW 5.12. I called the SC, and the tech advised to pull a fuse. This worked initially, but the AC went back to wimpy(was ice cold before the SC visit, amd the new FW). I have done a few hard resets, and it helps, for a while...
So now the car still shreads tires(coil suspension car), and the AC doesn't work. I really hate complaining, and am willing to live with those things, and whatever else crops up, but there is no ***** way on this planet that I will live with not getting the full 40A charging that I paid for(every stinking time). I'm a big boy, and can take responsibility for picking outlets that are safe. I don't need Tesla to dial back the current just because the UMC isn't designed for charging at 40A in the summertime.
I guess the moral of the story is, that Tesla is pretty much doomed if they keep on ******** on their most loyal customers who rant and rave. I kind of feel like a fool for writing such a big check for a car whose features get taken back little by little. After all I have been through with this car(the most problems I have had with a car, and I've had dozens), I still love it. I really wish I could go back to that 5.8 1.49.24 FW(I'm 100% sure that will fix the charging problem), but I already know that won't happen. That would make too much sense. Would I do it again? I'm not so sure anymore. The company has changed so much, and all of it has been for the worse. Anyway, it pains me to have written this, as I really do want Tesla to keep on getting bigger and better, but I really don't see how that is going to possible. They just don't seem to learn, and keep making the same mistakes over and over again.
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I don't understand why you are assuming that Tesla chose to limit current or that Tesla did anything or is taking something back. There is a problem with your one car (or perhaps your UMC) that is not generalized over the tens of thousands of cars on 6.1. In fact there are reports that with the latest builds of 6.1 the reduction of current when the car senses a voltage drop is no longer permanent for that session, but rather the car tries to increase the current again.
Something of yours is broken, whether it was caused by 6.1 in your specific car or the timing was just a coincidence, but there is certainly no evidence of a change in 6.1 that impairs charging.
See my long winded post. There is nothing wrong with the car, it's all firmware.
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I personally believe the entire "reduce current in response to voltage drop" is something that makes some sense from a safety/liability perspective... but at the same time there NEEDS to be an option to disable this nonsense. If I set the car to charge at X amps, I want the thing to pull X amps at whatever the heck voltage I feed it.
I've noticed more issue with this lately here in my development at night when it gets < 20F. Most homes in my area are electric heat pumps with resistive aux heat. So, at 18F everyone's aux heat is coming on. This makes some pretty good voltage sags shine through for a few moments at times as things on the service side catch up with the load, regardless of what load I have going on. (The graph of voltage I have for the past couple of weeks looks like noise...) Even a temporary dip in voltage is enough to trigger Tesla's annoying charging speed reduction algorithm.
I have, however, never had the car completely refuse to charge or stop charging...
But in any case, they need to have an option to disable this "feature." I don't care if it has to be done at a service center and I have to sign a waiver for them to do it, it needs to be able to be disabled.
Edit: I feel that it is worth pointing out that once the car is up to full amperage, the voltage drops it sees will likely have nothing whatsoever to do with the charging demand. I fail to see how having this algorithm active once the car is up to full power makes much sense. There isn't magically going to be more resistance in the line from car->EVSE->breaker just because the voltage drops from some load elsewhere. If the voltage sags too much an upstream breaker will trip if there is too much load. This.... really isn't the car's problem and it should stay out of it.
+10000000000
If somebody's garage burns down because of jerry-rigged wiring, its not Tesla's problem. The real problem is blame. Since UMC's melt like marshmallows, they are going to be blamed everytime. To me the solution is simple, too bad that ship sailed a long time ago. Tesla is simply not going to replace 70k UMC's with a more reliable, robust unit.
