Yes, about 4 months ago on my Seagull. I was riding along and it just died. I had to peddle that beast about a mile. So, they first sent me a new contol unit, which I installed. The battery had a blown fuse also. They sent me a new battery as well. I wired the controller wrong, mixed two colors, and it would not work. I found the problem, and now it works great. Did you check the fuse? There is just one, and it's impossible to find a replacement. Ecotric has none, and they kept sending me the wrong size. The correct fuse is a ceramic 30 amp-250 volt, mini fuse-20 mm. (3/4 inch). This is a super rare fuse. You won't fnd one online or anywhere else. BUT, I just found a source for a replacement. It's glass, not ceramic, which is fine, and they will be coming in a two weeks at Electricscooterparts.com. Buy some before their gone! So, if you used a multimeter and the fuse is good, and you installed the control box wires correctly, and you have checked the volts of the new battery (48) and it's good, then I have no idea what the problem could be. If it's still under warranty I would send it back before the 18 months is up. Just get a new one. Mine is just over one year, still under warranty. Hope that helps.