It does sound as if the 2-pin ribbon cable has become disconnected. To reconnect it you’ll have to remove the top cover of the unit. MAKE SURE THE POWER IS DISCONNECTED FIRST. Once the cover is off, you’ll see the cable poking through the front panel assembly between the transformers. There is a two-pin connector, facing the bottom, on the small board that the LED’s are soldered to. Simply connect the ribbon cable to this connector, and you should be rolling. If you wish to remove the handles, they should be removed one at a time, and shorter screws inserted to attach the top and bottom caps to the amp. We can send you the proper screws if you want.
james