Fuse Box "B+" led indicator wrong

Inside the 912iS Fuse Box there are 2 large fuses. One 35Amps for "B" generator and other of 20Amps for "A" generator. When the Side A fuse is blown or removed, the green led indicator next to it (labeled H20) goes off (as expected), however whe the same action is done on the Side B fuse, led indicator stills is in green, however the fuse is gone. Has anyone had this problem ??