[joedoh]

ok some background:

cigarette lighters were originally cigarette lighters, in older gm cars and trucks they were typically on the same circuit as the dome light and fused in the fusebox at 20A.

the way a cigarette lighter works is, on the socket the outside barrel is ground and the center pin is 12v+. when you push the lighter in, there is a bimetal spring that is in contact with the outer barrel of the lighter and the center of the spring contacts the 12V+ pin creating a dead short through the spring. this short heats the bimetal spring until it changes shape enough to "pop" the lighter off the center pin. the spring stays hot enough to light a cigarette.

most cars since the late 90s have only had a "power port" socket which is in the same shape as a cigarette lighter but is lower amperage and cant handle the heat of a lighter, being mostly plastic. heavy and metal socket = lighter, light and plastic socket = power port.

if you are blowing a 30A fuse as soon as you plug it in, you either have a lighter in a power port, the center pins are slightly different and the lighter will bypass the bimetal spring and the fuse will see a dead short = blown fuse, or you have a bad lighter that has a broken spring and = dead short.

I put power ports in all my trucks, they fit in the place of the original lighter AND the original key, so I usually double up. I wouldnt use a lighter in them. there is a lighter in the s10s (a holdover?) ashtray, but I rarely take it apart far enough to get it out.