What does a yellow and green light mean on my Generac generator?

A green light means that your Generac generator is working correctly. A yellow light means that your generator needs maintenance, but is still running as programmed. In some cases, a yellow light can also mean that the battery charger isn't charging well. When they're both on together, this just means that your generator is running fine, but you may need a technician to come look at to prevent any future issues. A red light means that something has gone wrong and your generator isn't working.