Well start at the known issue; odd sensor value.

When my e seventy was aiming the headlights incorrectly i used realtime monitoring of the level sensor to determine the bar was the wrong one.

Disconnect the bar and sweep the lever while monitoring.

Disconnect the air compressor at the compressor so you can have the fuses in but it won't run the compressor all the time.

Maybe disconnect the ground if it's not a plug so you don't short it out.

Shorting the power to ground is the easiest way to determine which fuse is actually powering the thing though going through fifty fuses might not be "easy".

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2011 E70 • N55 (me)
2012 E70 • N63 (wife)