I give up, advisors assemble! Lighter fuse?

Was that fuse from the under hood box or the under dash box, because under the dash should be all low profile mini, and that is what the discussion is about, under dash box.
Also, that pic you have here is not the proper terms for those fuses.

 

Have you, or has someone installed anything ? Has anything been added to the circuit ? With a voltmeter try probing the center of the power socket with a good fuse and get ground at the first try from a bolt holding the seats to the floor. If you read voltage there, then try for a ground at the lighter body . That power take off, isn't loose by any chance is it ?

If you don't have a multimeter I bought one at walmart as GE 2425, so so I could have a same meter to chat with on line. Guys that bought one asked me about settings and how to test for years now. I didn't do this with cars as much as I did with Kawasaki Nomad bikes, but 12 volts is 12 volts, only the Nomads are harder. They have 2 alternators and 18 diodes between them and the 2 rectifier regulators, on a brushless system .

They have one advantage we don't, which is a in color papr wiring diagram .