On mine the box is at the end of the cable that has the 7 pin plug on the end. It is screwed on the front of the frame at the back of the A frame. Yours may be in a different place but that big 7 pin cable should be traceable to a junction box somewhere.
2017 SLX 195RB
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Andersen WDH hitch, Renogy 100 AH Lithium &
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