Hi I have a Coachmen Freelander RV built on a 2016 Chevy Express 4500 chassis. There is a starter relay that connects the two batteries this chassis (one in the engine compartment, the other under the chassis low to the ground). On the terminal of the starter relay where the 2nd battery is connected, is another wire that goes through an inline fuse, to a small third fuse box located near the air-filter. I cannot find any information on this third fuse box or what its for. The third fuse box seems to distribute a bundle of wires through the engine compartment on the drivers side. Does anyone know what this third fuse box is for?

 

I have seen that before, I thought it was the third-party upfitter optional fuseblock, but I don't know.

You can look through here.
https://www.gmupfitter.com/wp-conten...2016_en_US.pdf


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