Changing the battery is very simple on the non-pro version of the Behringer Bass V-Amp (the one that looks like a guitar body, not the one that’s rack-mountable).
Preparation: Unplug the unit – do not have any power going to this unit during this work, in case you drop the battery onto the circuit board when it’s under power – that could short things out and fry something important, after which you’ll be sad.To open the unit:
Place the unit upside down on a soft surface like a few layers of towel, or a pillow, so the buttons and dials cannot be damaged.
1 – Undo the 5 self-tapping screws in the bottom with a medium Philips screwdriver, set them aside.
2 – Open the bottom of the case carefully. You’ll see the CR2032 coin-like battery in a clip on the circuit board. Carefully push it toward the v-shaped spring and pry up.
3 – Remove and discard the old battery in an eco-friendly way – use battery recycling facilities wherever possible, these lithium batteries are not suitable for ordinary garbage. If the old battery had leaked a bit, clean the gunge with a Q-Tip dipped in rubbing alcohol until it’s quite clean. Check for corroded leads if the leakage had been really extensive, and carefully solder those if possible.
4 – Insert a new battery, place the screws back in the holes and tighten them carefully until just barely firm – since they’re going into plastic, over-tightening them will just strip the screw holes and nothing will hold after that without fixing the holes to give the screw threads something new to grip.
I usually write the battery’s expected expiry date (or best before date) with a fine -point permanent market on the battery itself, and also leave myself a notation on a piece of tape stuck to the bottom of the unit as to when I can reasonably expect to have to replace the battery.