Trouble with electric hatch actuators
 

Just bought an old 98 outlaw 25' and am having some trouble with the electric hatch.One side seems to work but the other side dosent work so well. When the engine is running and charging at 14 volts they seem ok. Batteries start the engine fine so i dont think their low. any suggestions? Problem is
when engine not running,even with battery charger hooked up.
Can they be rebuilt?