12V Access: Model S 2021 Refresh

[4SUPER9]

I have a fuse box that is tapped directly into the li-ion battery. "Tapped" is a strong word. I have a 16G wire that I stripped approximately 4" and wrapped it around the post many times, then forced the cap back on. I heard others (maybe upthread?) who drilled into that post. This post is definitely always on. As far as amperage, I don't know. Since it is directly off the battery, I can't imagine you will find more than this elsewhere.

 

[n2mb_racing]

I have a fuse box that is tapped directly into the li-ion battery. "Tapped" is a strong word. I have a 16G wire that I stripped approximately 4" and wrapped it around the post many times, then forced the cap back on. I heard others (maybe upthread?) who drilled into that post. This post is definitely always on. As far as amperage, I don't know. Since it is directly off the battery, I can't imagine you will find more than this elsewhere.

Direct to the DC DC converter would allow more power, but I don't know where to get it. The DC DC is not directly connected to the battery.

 

[vcor]

The battery is monitored, and if low, the DC-DC charger will be turned on to charge the battery (and provide power to other items you may have connected). As this is all driven by software, if it sees the need to charge the 16v battery more frequently than it expects, due to a significant external load, it might identify the 16v battery as starting to fail and flag an unnecessary service warning that can likely be ignored.

 

[n2mb_racing]

The battery is monitored, and if low, the DC-DC charger will be turned on to charge the battery (and provide power to other items you may have connected). As this is all driven by software, if it sees the need to charge the 16v battery more frequently than it expects, due to a significant external load, it might identify the 16v battery as starting to fail and flag an unnecessary service warning that can likely be ignored.

I wonder how much charging current they provide. I can't imagine much reason for them to charge the 16v battery very quickly. So I'd guess 7A to 14A.

 

[myblubu]

It’s down at the bottom of the area behind the carpet in front of the left footrest. Remove the small cover/panel in the first picture - pull from the top. Then lift the carpet and door sill up and in to expose the area where the connector is. Hopefully the pictures help. Good luck and let me know if you need any help - I’ll try.

THANKS to everyone who mentioned the brake controller!!!! This was VERY helpful! I have a 2020 MY Performance and wanted to install my V1 in it hardwired as I have in my MX. Blendmount recently made the mount for my MY available, so I bought one and installed it, but finding 12 V power was a challenge. I had watched a few YouTube videos about finding a magical red wire on the passenger side footwell in the bundle of a zillion wires. I tested every red one and almost all of the rest and I couldn't find a wire with 15V. I made the mistake of securing the wire with wire ties all the way from the headliner to the footwell area (it was a very neat job if I do say so myself) but when I couldn't find power, I had to undo everything and run the wire to the opposite side of the car (driver's side). Removing the trim, the brake controller connector was right there in plain sight. I bought the wire harness from Tesla, they assumed it was for my MX and it only cost $4.73 including tax (cheapest thing I've ever bought from Tesla!) But I would have gladly paid 10X that for the convenience it provided and not having to tap into any wires, etc. Plugged it in and tested the red and black wires - 12V switched! V1 is installed and working great.

Thanks for the tip on the harness!!!