I have a custom box with 4 10" L7s. I have a second optima battery in the box. I need to replace one of the subs that i blew. Is there anything special that i need to do to so i dont get electrocuted or short out my system because of the second battery?

 

just keep the key off.the speakers will have no power if the key is off and if some how the speaker wire touches the batt wire (which they wont) nothing will happen.

 

if there is a fuse in the power cable line you can take it out if you want but it wont hurt you to chane the speaker out. Do you have a single cab truck or a quad cab i have 1 12" L7 in my single cab

 

Its a quad cab and I ripped out the back seats, because there is only enough room for a 12 year old back there. And thanks for the help, I was woried because ive heard stories of having to drain the capacitor i thought it was the same thing with the battery

 

Do you have a capacitor on there?

If no and you are that worried about it just discconect the battery.