I would wait awhile, I mean, like I said, I really don't know how or why mine worked for 1 day, and then crapped out again. Like some others who have posted here, it's only a circuit board, and you'd think it would either work or not, ever, period. But then again, remember when your dad smacked the old B/W tv set a few times and the picture would come in PERFECT ??? Go figure. Some things never change I guess.
I don't know about whether disconnecting the negative terminals helps, hurts, or no change. I replaced mine (4x4CM) and I didn't disconnect anything. I figured that's what got me here in the first place. Maybe someone else knows. I kind of figure it's got to be like any other appliance. It's probably BEST to disconnect any appliance from the power source before messing around with it, but if you are just replacing one "light bulb" for another one, either way, when you reconnect the battery, the power is going to flow thru the appliance anyway as if you never disconnected in the first place, so..... good luck, either way!