Green is good on those indicator lights. If the new model T is like the 300T, the lights are to indicate when a fuse has blown. One light per pair of tubes. Red means you have blown a fuse - your amp should still work-just using the remaining tube pair that don't connect to the blown fuse and connect to the remaining good fuse. Green should indicate the fuses are working properly. Also, in standbye mode the lights should always be red. Is your amp working, and your just concerned about the green lights, or is the head still dead?