Keep it plugged in or let it run down?

[FlatSix911]

All these posts and the original hypothetical was never answered.

In general, I'd say that if you run out of the ability to drive, the battery pack still has that bricking reserve left. Not sure if it routes any energy to the 12v at that point. But, if you get it to a charger somehow then it should start charging. If your main battery is dead (not fully bricked) and your 12v is also dead... then I'd say you're screwed fully. You would have to have the 12v replaced likely first before anything is possible with the main battery again since all electronics/controllers in the car would be dead.

If your 12V battery is discharged you just need to locate the 12v terminals behind the nose cone on classic cars or at the battery on facelift cars. Attach another 12v source to recharge and then gain entry to the car so you can start recharging the main traction battery.

 

[travwill]

If your 12V battery is discharged you just need to locate the 12v terminals behind the nose cone on classic cars or at the battery on facelift cars. Attach another 12v source to recharge and then gain entry to the car so you can start recharging the main traction battery.

Yeah I guess you could charge the battery if it is in good health still or even temporarily. On the X and S (current), the terminals require you to open the frunk (so you would have to use that manual hidden release), take off the cover in front that covers fuse terminal and area closest to windshield, then one positive terminal is on right, and a ground is on left of car - very specific/odd connections.

The instructions are on the fuse relay cover when needed.

 

[Rocky_H]

I live in a condo and we are installing a small number of chargers. People say we should share them, but I'm worried about the "Keep it plugged in" mantra; other owners say that doesn't make sense and i should ignore it. So: 1. is there a way to find out what the actual purpose of keeping it plugged in is, that would satisfy engineer types? and 2. is keeping it plugged into 110 V sufficient for this purpose? --New, intimidated model 3 owner.

First off, don't worry--it's not really necessary--just a little helpful, which is why they recommend it.
There are two main reasons they say that:
(1) There seemed to be this old mythical idea among people who don't know electric cars that keeping the car plugged in all the time is dangerous or harmful to it. They imagined that the charging cable is always trying to "force" energy into the car, and that if they didn't hurry and unplug it when it was full, the cable was going to keep trying to jam energy into it until the car exploded. Tesla is trying to dispel that myth and let people know not to fear keeping it plugged in, and to do it as often as they want.
(2) They don't want to give people a bad impression of electric cars of being defective and inconvenient. So if people were trying to do this thing of intentionally running it low before plugging in, and then they find they need to drive 84 miles away on short notice, and the car was down at 26%, then they don't have enough range, and it's a pain in the butt, and "Why did I buy this stupid electric car?!" Tesla really doesn't want those kinds of stories popping up frequently, and for people to be disappointed in the experience by not having enough range.

The main things for the batteries are just to not spend a lot of time near 0% or 100%. But if you're staying somewhat near the middle most of the time, the car will be fine whether it's plugged in or not. So if it goes a few days between plugging in, but you're still only getting down to 30 or 40%, that is still no problem.

 

[SongjinDK]

I think one benefit of plugging in is that the car can use more engergy to keep the battery cool. If not plugged, BMS may not be able to cool it as much to avoid reducing too much range. High temperature is worse to the battery So even if you don't need the extra range, you can set limit to 60% or even 50% and leave it plugged, especially on vacations.

 

[nwdiver]

I live in a condo and we are installing a small number of chargers. People say we should share them, but I'm worried about the "Keep it plugged in" mantra; other owners say that doesn't make sense and i should ignore it. So: 1. is there a way to find out what the actual purpose of keeping it plugged in is, that would satisfy engineer types? and 2. is keeping it plugged into 110 V sufficient for this purpose? --New, intimidated model 3 owner.

If infrastructure is being installed there's really no cost savings with 110v vs 208/240v. The ideal solution is to have as many plugs as possible so cars can stay plugged in. There's lots of load sharing solutions available OF if you're trying to be super thrifty install NEMA 6-20s.