Power failure on fan 6 is reported when the measured fan speed doesn’t reach the expected speed.
If this error message is shown in the monitoring tab of the WebUI when the Fan is only starting to spin, it is not a failure as such. When the controller activates the Fan, the ISP reads the Fan speed and compare it to the expected speed. The whole start up process is then seen as a failure, until the Fan reaches the stabilized and expected speed.
If the message is prompted on the display and the WebUI after the Init process is complete, then it is a real issue that may need assistance. You can then open a ticket on our Service Desk.