Trickle charger won't light up?

[springer123]

I had my alternator replaced last week. The battery was ok, so that wasn't changed.
I hooked up my Porsche trickle charger through the cigarette lighter like I always do, and the top light won't light up? When I push the mode button on the charger the light moves to the car setting, that works, but the top light won't light up. It always started out on orange and then moved to green when the battery was charged. Now nothing on the top light. I checked the cigarette fuse, that's ok. I replaced the fuse in the Porsche trickle charger but the top light will still not light up? Any ideas as to what could be wrong? It has to be something related to the alternator change?