Good morning need to now what is fuse num 17 in my truck ford explorer xls. as soon is i try to put a fuse it pops

Fuse 17 is the cigarette lighter. Check to see if a coin fell into the cigarette lighter socket before replacing fuse.

Hello, This 25 Amp fuse(#17) is for your cigarette lighter socket. If you used the socket for something else, you may have bent the terminals inside it. You will need to replace this socket as it is shorting out.

This should not be too expensive. Sometimes the autoparts stores have a display of HELP products for typical repairs and a socket going bad is common.