Parking Brake light won't turn off.

Strong possibility the master cylinder just needs more brake fluid added. Low brake fluid level will illuminate that same light.

This is an easy fix and most DIY'ers can solve the problem: Head to your toolbox and find your black electrical tape. Cut a 1" long piece of said tape. Now sit in your driver's seat with the cut piece of tape in hand. Place this piece of tape strategically over the parking brake light. Problem solved.