You may sometimes notice that one or both fans on your EX90 are running high. Depending on the amount of ambient noise in your environment, this may or may not be distracting.
In some cases, the software that controls fan speed has lost contact with the fans, so the fans run high as a precaution. This loss of contact often occurs when there is a brief interruption of power to the EX90 -- due to an external power flicker or a loose cable.
Checking the status of the fans via the CLI, you'll often see the following:
*s SystemUnit Hardware Monitoring Fan 1 Status: "not present"
*s SystemUnit Hardware Monitoring Fan 2 Status: "not present"
To get the EX90 back to normal, the power cord must be removed and then replaced after a few seconds (i.e., it must be hard power cycled.) Simply powering the system down with the power button won't resolve the problem.
There can, of course, be other causes of loud fans, but if you run into an EX90 with this problem, hard power cycling is worth a try.
