hooked up bettery wrong

[dmgarirson87]

I hooked my [COLOR=green! important][COLOR=green! important]battery[/color][/color] up backwards pos to neg and neg to pos only for a few seconds. A black box behind my battery smoked I never started the car while it was hooked up wrong nor were the keys in it. After that happened we realized it was hooked up wrong, so we hooked it up right and now accessories come on but the car wont turn over. It just clicks like the battery is dead but the battery was checked and is fine as well as the starter. There dont seem to be any melted wires going into the box that smoked.We also replaced the fusible links off the battery cable. Do you have any idea what else could be causing it not to start?