There is no way to tell when a lamp is dead on a projector. The blink code may let you know that the projector is detecting a lamp issue, but it has a number of issues which it could be that are not the lamp. Likewise, there is no visible way to tell with projector lamps if they are actually good or not. It's not like a lightbulb in your home with a blown filament. High pressure lamps, like projectors use, don't work the same way and don't have physical signs of being 'burnt out'. So, you just have to get a new lamp and see if that fixes the issue.