Car battery float charger goes straight to float mode though battery is dead?

I recently purchased a Stanley 6v float charger because my 2 year old honda battery died

pretty sure the battery was the problem since the car started fine with a jumpstart but when i took the battery out the car and plugged the charger on it, went straight to green light/charged/float mode on LED display

ever seen that happen or know what's going on maybe? I'm gunna leave it plugged in over night on float mode and hope for the best

A Honda car that runs on 6 volts? Thought they were all 12 volts. Maybe that could be why it doesn't work?

Sorry, I meant to say 6amp not volt, it says it does vehicles with 12v batteries

Battery is most likely shorted, unusable