That's why I hate those smart chargers, they are brain dead!
Mine will give an error and not turn on if the battery is too low (dead), I have to jump the car to charge the battery, then use the charger.
Energy efficient means uses power when turned off, Smart means brain dead. Must be the yuppie kids making products that think "That's BAD Dude" means great and cool
I just love those "Smart" things.... NOT
Harbor Frieght still sells the old fashioned ones that work when turned on!
If you want low amps, 2/4/6 etc.. check them, I think I saw them in the Springfield store, catalog, and online. Various amp sizes, not as HIGH as I wanted though, I wanted 40amps for larger banks and batteries. Thinking about buying one though so I can charge the batteries enough that the "Smart Charger" will turn on.
Real pain if the car lights are left on and the battery charger won't work till AFTER I charge the battery.