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Can you disconnect and reconnect the 12 volt battery without causing any problems?

Can you disconnect and reconnect the 12 volt battery without causing any problems?

bill | 7 Janvier 2020

I am going to add some 12 volt plugs to my Frunk for a 12 volt refrigerator freezer. I thought I would add a fuse block with about 8 fuses and connections somewhere possibly in the Frunk for easy access and connect it directly to the 12 volt battery. Ideally you would disconnect the ground first to prevent any shorting and then add some wires with eye connectors to one of the terminal lugs on the battery. If I disconnect and reconnect will it cause me to loose any settings? Will the car power back up without needing any reconfiguration?

bill | 7 Janvier 2020

Also is there a better way to tap the 12 volts and not potentially overload a circuit if you tap a wire?

I noticed there is a lead on the other side of the fuse block above the battery that has a 250 AMP fuse. I was wondering if this might be the connection to charge the batter from the main battery? Since it should be 12 volts that might be a good place to connect and if I am careful I can avoid disconnecting the car. Any thoughts?

jordanrichard | 8 Janvier 2020

Is your car still under warranty? If not, I wouldn't touch it or have someone else do the install so that should something go wrong, they can cover the cost of fixing whatever unintended things happen.

GoldAK47 | 8 Janvier 2020

You can disconnect it, and the HV battery with no issue.

I would not connect anything extra to the battery. Unless you are transporting Chuck Norris DNA in that freezer, its not worth it.

jimglas | 8 Janvier 2020

EM DNA, then....maybe

bill | 8 Janvier 2020

The car is out of Warranted and Tesla SC won't do anything like this. I would rather do it myself and be careful rather then rely on a 3rd party shop to fix a problem they created.

GoldAK47 | 8 Janvier 2020

Thats not the problem. Adding draw to the system is the problem. Why is adding a freezer to your car a problem Tesla created?

You can disconnect battery, Ive done it dozens of times for weeks at a time.

Bighorn | 8 Janvier 2020

I’ve seen hard wired fridges in an S. Just be aware of the constraints of what’s essentially a motorcycle battery.

TeslaTap.com | 8 Janvier 2020

@bill - I don't see much warranty risk. At worse they could void the 12v battery for overuse, but I doubt it. I'd limit the draw to under 50 amps, assuming fairly short periods. For continuous power, I'd cut that in half - perhaps 25 amps max. More of a WAG on my part, and not anything I've heard directly from Tesla. I'd avoid this altogether if using an old S with a poor battery location. My concern about the oldest cars is the DC-DC inverter doesn't have the most robust design. If it blows, due to having too large of a current drain, it is costly to replace. Newer cars greatly improved the design and are far less likely to have any problems.