Unused 40A fuse location?

[TouringM3]

Hey pals –

I write to you from the wiring wasteland.

Turns out that the F80's active rear diff shares the same 40A fuse location as the F31 power tailgate.

So, i need to find a new location to plug in the power tailgate.


Does anyone here know how to discern which fuse locations are open and can provide 40A?

I've looked at this thread here, but couldn't figure out if I can just pop-in whatever fuse I want to an open slot, or if only certain slots can accommodate 40A.
https://f80.bimmerpost.com/forums/sh....php?t=1413253


THANKS!

[WagonR]

A couple of thoughts, but I don't know the specific answer:

1) The way those fuse blocks work is by brining power in, and then the circuit board distributes power to one side of the fuse holders. There are multiple power sources, so the circuit board distributes to specific fused per power source. Usually fuses are grouped together based on the power in source, so in that example you linked to, the rear fuse block likely could have fuses 105 to 111 with the same power source. In theory you might be able to use one of the open slots to add in a new fuse; however,

2) I tried to add in a fuse to the fuse block in my X3, and I learned two something. If the fuse wasn't' there form the factory the circuit board in the fuse panel doesn't even have the fuse holder in it. In my case, to have a fuse in the board itself, I bought a second one, de-soldered a fuse holder and soldered it into the board to add a place for the fuse. Additionally, the harness that plugs into the fuse block that takes the power form the fuse out to the electronic item didn't have wires in the pins that didn't have fuses, so I had to get a connector for that. You should be able to test this by seeing if you can put a fuse into an empty space. In my case, since the fuse holder wasn't originally in the board, it just fell out until I modified it.

3) Amperage considerations. I'm sure BMW divides the power sources and outputs in the fuse block by some total amperage rating. Adding 2 40amp fuses to a block not designed for it could potentially be a problem; however, since one is the diff, and one is the rear gate, I would assume they're not going to be operating at the same time...so it should be fine.

[TouringM3]

Awesome, your thoughts on #3 were the same as mine, so fingers crossed on that.