Cigarette lighter plug is shorting, or the wires probably are. I've seen more problems with those than my dog has fleas.
With everything off, use an ammeter (one that's a high-precision on a digital volt meter), and trace current drain back to the block, then use the accessories, and monitor current flow. The part that's sucking too much power is faulty, or the wiring is. It's tedious, but it works. Good luck to you!