No. If you plug your charger into the wall but not plug it into the receptacle on your golf cart, you will not see any  signs of life from the charger (i.e. humming, buzzing, heating up, lights coming on, etc.). The plug on your golf cart charger needs to make connection with the holes/leads within the receptacle on your golf cart in order to kick on. The charger needs to be connected to battery voltage. Even if you connect up a volt-meter to the charger, it will not give off any voltage. So in short, the charger will not do anything without being connected to your golf cart.