Many vehicles, especially those used for utility and dependability, run and use dual batteries. So it is important to be able to quickly and effectively charge both of these batteries. The process is quite simple and requires only basic tools.
Pull the vehicle into an open, accessible location, if possible, and open its hood. Make sure the hood is secured in the open position.
Locate both batteries in the compartment area. Then, using steel wool, clean all the connection ends on the electrical surfaces of the battery posts. It is wise to do this often to keep the batteries running correctly and to make quick charging more effective.
Find the bridge switch between the two batteries (usually located on a lead just off the main battery), and make sure the switch is turned on. This will connect the two batteries, and make their capacities charge and discharge evenly.
Plug a standard automotive battery charger into a 110-volt wall plug, and then connect its charging ends to the posts on the main battery. Make sure to match up positive (red) and negative (black) end clamps with the proper battery posts.
Switch the adjustment knob on the charger to the 4-volt setting. Then, allow the batteries to charge for one to two hours.
Unplug the battery charger, and unclip its charging clamps from the battery's posts. Then, close the vehicle's hood.
