Troubleshooting Unresponsiveness in APC Back-UPS 600: Power Button Issue

[Jay1202]

Hello everyone, I need some help with my APC Back-UPS 600. I've attached a photo for reference, as I couldn't understand what's happening to it. The power button is unresponsive; in fact, the whole UPS is just dead with lights on. Nothing happens when I press the button, try a hard reset, or even plug it into the socket. I personally opened the UPS after having the problem and disconnected and reconnected the battery. Still, the issue remains the same.

[JReese3]

I have 3 of these small APC UPS Back-ups 600 models for home use. One has failed like yours has after 8 months.  Would have to troubleshoot it with a meter and possibly fully disassemble to find root cause.  Could be as simple as a failed solder.

[Manab]

I have the same problem. Any hints at possible solutions?