For a cheap quick way of checking for 12 volts thru a fuse, a 12 volt test light is what I'd use....connect the alligator clip to the batt. neg on the panel in your pic, and use probe to see if current is really passing thru fuse....on the face of fuse, there is a little metal area show'n, on each side on face, that you can probe...if light lights, fuse is good
Bob/Linda, 99 Dodge 2500 Cummins,2010 8280 Rockwood Ultra-lite 5er, PullRite Superglide-----
I'm retired......but work part time as a pain in the ass!........... USMC.