Just open the fuse box and see if the fuse for the high blower is still in service; the upgrade was to replace the existing fuse with a separate fuse in a holder, wired to the blower circuit. You can remove the two Phillips screws and lift the fuse panel; the blower wire is attached to the bottom fuse terminal with a Phillips screw. Take it off and attach a fuse holder; M-B recommended an increase to a 30A fuse, but I kept the 25A. I did not want to take too much chance with a 20-year-old car's wiring, and the problem was caused by the terminal overheating and melting the fuse block, not by blowing the fuse. The 25A has worked fine for me. You can buy a fuse holder at a parts store; I used a typical modern auto fuse. Simple. You can buy the "official" fuse holder and fuse at a dealer if you prefer.