Logitech M705: How to fix a defective mouse button

After cleaning and reassembling...

I’m a big fan of Logitech mice, or at least was until a few days ago. My wireless Logitech M705 started to behave strangely: Pressing down the left mouse button resulted in multiple clicks (i.e. double-clicking) and dragging became impossible due to random interruptions when holding down the button.

Without a warranty (which had expired three months ago) I did not feel guilty when opening the mouse to look for the cause. The culprit was quickly found: the microswitch of the left mouse button. Luckily, I had spare microswitches as I’m currently playing around with the optical sensors from other spare/defective mice. I will cover this in another post. To come to the point: after replacing the microswitch, the mouse works again as usual. I’ve made a few photos (a picture is worth a thousand words 😉 ) to help others during disassembly of the housing. Screws are marked red, and I have also marked (in yellow) two tiny springs that can easily be lost.

This fix has a bad aftertaste: at least in Germany, there is much talk about “planned obsolescence”, and I’m wondering if Logitech (and other manufacturers) use cheap microswitches that only survive a certain number of clicks. Especially after my mouse showed the previously mentioned defect so soon after the expiry of the warranty… On the other hand Logitech kept its promise regarding the battery life – I’m still using the first set.

Update (2014-11-22): Just as a brief clarification, after I got some feedback on the M705. (Apparently several users have had similar experiences.) Logitech uses Omron switches that actually seem to be pretty good. So I want to point to posts from Kogos and Ralf  below: First you should try what is recommended in a Logitech forum post. After that you might try resoldering the joints. If that doesn’t help an exchange might be the best option…