parking brake light and top issues

[tk-4]

hi, i have a 2000 boxster and over the weekend my top was stuck in the open position. after a couple of days surfing various boxster forums, i realized that it's my parking brake that's causing the problem. when i pull on the parking brake the light only goes on sometimes. does anyone know what's causing the light and hence the top to work at certain times and not the rest? is this something i can fix myself? and if i bring it back to the dealership to check it out, will they charge me an arm and a leg for it?

i've read posts bout relays and micro-switches but am completely lost.

thanks for your help.