Depends if it's blinking or solid.
LED Indicator Descriptions AI-Fi Lights
Overview All AI-Fi Lights have a LED indicator that utilizes red/green/blue to indicate several states. Below you will find a description of each LED indicator state. Blinking Blue/Green (alternat...support.aquaillumination.com
If it is red/pink, clean it first though. Could just be crud.
When the fans fail, there is a grinding noise before they die.