Apparently a 0.15 V drop on this battery is enough to stop the keyboard working. I measured the voltage and it reflects marginally over 3.03 V. So I popped my battery out of my new keyboard, and lo and behold it worked. I tested some other components but couldn’t find anything notably wrong with the board. With my old battery plugged in, V_BAT showed 2.86 V and V_MAIN showed a steady 2.0 V. So to disassemble it you have to pry that off, making reassembly difficult.Īfter that there are a number of screws to remove, and then the base separates, giving you access to the circuit-board. Although the battery comes out relatively easily, the keyboard’s faceplate is glued into place. I found it the other day and decided to take another look. I figured I’d salvage the solar panels or something. This was over a year ago in-between a lot has happened, but Logitech didn’t ask me to return the old keyboard, and I couldn’t bring myself to throw it out. The keyboard had a 3-year warranty I was still within, so after the retailer rejected me, I contacted Logitech who were kind enough to send me a replacement that continues to work perfectly. My battery measured 2.9V, so I assumed it was still fine, and something else had gone wrong. The battery used is a rechargeable coin-cell battery, similar to what is used on motherboards, an ML2032 3.0V battery. The battery is not supposed to be replaced, but is relatively easily accessible, so I popped it out and measured the voltage. Not registering keypresses, nor activating any of it’s notification lights. Two years later, on returning from a short trip, the keyboard no longer worked. So joyous was I to find it on a half-price special at some stage, promptly ordering it and enjoying it’s use. Besides that it’s a standard wireless keyboard that uses Logitech’s unifying receiver, I additionally like the style and design of the keyboard. A dream come true to me, who in general is disposable battery averse. This should mean you never have to replace the battery. It’s most noticeable feature is the fact that it has a bar of solar panels along the top of the board which are used to charge the built in battery. Since the Logitech K750 was first released, I was a fan. Tl dr: Thought keyboard was broken, only needed battery replacement.