I replaced my own battery heater

[Iz]

Battery heater just went on my 2013 MS (formerly 60kWh, now 75kWh). Going to attempt the surgery in a few weeks. Vehicle does not charge when temperatures are low. Fireman's loop connector is a concern.

 

[Anthony R.]

I love home-made ingenuity and resourcefulness, nice job OP.

Now, can you please share how you disconnected the first responder loop? I was thinking of doing a BMS reset on my 2020 Model S via the service menu, but that requires the contactors to be open and I believe disconnecting the first responder loop will open the contactors?

For my early S (2014 RWD) you can get to the cut loop connector by taking the cabin air filter box out the same way you would when disconnecting the battery. Which you should be doing anyway when working with HV, just to be safe.
You can see the loop and connector in this video:

 

[walla2]

So does it have to match what they have? The part number they put on the estimate ends with a K. Would a heater that ends in a G work?

If your part was a F and the service centered wanted to use a K but the current Tesla's use a M, I would favor trying F-K parts but not a L or M as something probably changed at L hence the reason Tesla favors the K over a newer one that might not be compatible. The advantage to choosing a K might be that it exists for a reason, F's might not be as great of a design and design changes have occurred to extend life of the part with less failures (not necessarily true but ideally so).

Also looking at images of the connectors and part orientation is fairly important to make sure you don't have different plugs or a new angle to deal with along with other things less obvious internally.