I didn't have brasso at hand but decided to use a thin sand paper on the contact points after opening the cartridge. To my amazement they came to life on the screen but yet the controls did not work. For some reason some had the video lined up to the right or even broken up. One thing is sure, dirt and grime accumulated over the years on the contacts and also affected the chip itself. Weird that controllers don't work. I gave up. The ones that worked might had been people who had them in storage were humidity and exposure did not ruin them.