This is a short story, but search for solution was a little longer :)
Step 1: Background:
From day one i had an issue with this mouse loosing connection with computer randomly.
It happened on different PC-s so it was not computer related.
Also i have tried to reset it (with holding right button and clicking left for 5 times) but it didn't help.
What happened is that it suddenly wouldn't respond any more, and this state would last for several seconds. During this time it would blink with all three green lights and then red light would blink eight times. Sometimes it would only blink red. Sometimes only 3 green lights.
What is strange is that when it is connected with charging cable it works properly so i figured out that it must be something battery related. I have replaced GP ReCyko battery that came with mouse with genuine SANYO ENELOOP battery to test it. Unfortunately it had the same behavior with new battery.
Step 2: Troubleshooting:
Since i have narrowed problem down to power part i started troubleshooting. I ended up with outgoing part of booster malfunctioning. It is lifting voltage from 1.2V to 3V but it's oscillating and dropping to 0V causing disconnections!
So i used electrolytic capacitor laying around, connected it to PCB and voila! No more disconnections and blinking lights!
Step 3: Fix:
- soldering iron, one electrolytic capacitor (10uF 35V). You can use lower voltage, but don't go too low (booster is lifting voltage to 3V). Regarding capacitance, it is not critical but don't go too high (more than 100uF).
- solder plus part of capacitor to Q8 point on bottom part of PCB, minus part to black wire connection (usb lead). see picture for more info.
- alternately you can connect directly to booster output capacitors labeled C20 and C21 (on top part of PCB). Plus part of capacitor to inner point on capacitors, minus part to outer part of capacitors. See picture for more info.-
- make sure that you don't make short circuit with long uninsulated legs of capacitor. It is not visible in pictures but i made sure that they are quite far away from PCB board..
- i have added some glue to hold capacitor (mechanical stability).
Step 4: Final:
- mouse is working fine since repair without any issues!
- i have tried to post this on logitech forum, but my solution was deleted without explanation. So it must be a good one! And they are embarrassed even this is discontinued product, or they have similar problems with current products..
PS. This could be common issue with logitech wireless devices. So try it on other mice's, keyboards, remotes.. and post back if it works!!