Had etrailer install hitch and wiring harness for my 2023 Palisade. Looks like their harness plugged into factory harness but have no power. Looked under hood and there are 4 fuse spaces for trailer. 2 of them have no fuses. Do all 4 have to be in place or are the blank ones for a 7 pin hook up? Wiring looks good. Ground is solid.
