Some of these ATMs are now becoming many years old. The easiest preventative maintenance that you can do is change the UPS battery. According to APC, the battery should last 3-6 years but your mileage may vary.
All GenesisCoin ATMs have a APC Back-UPS 350 and the battery is a “APC Replacement Battery Cartridge #2”.
If you search Amazon for “RBC2” you can find cheaper batteries from third-party manufacturers too.
Here are the instructions to connect a battery:
Here is how you will know if your battery has failed: