Good Luck.
If you don't get an answer from Mercedes (They wouldn't touch mine) - Shine a light in the hole under your seat toward the back, there should be three red thick gauge wires that have rubber fuse blocks in them, I think the 7.5amp is the backup lights for rear of coach. If you can reach them from that opening it would be great, I have fat hands and couldn't though.
Good Luck with it.
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