Thank you for using the Support Forum. There are a couple of things you can check, first unplug the network cable from the printer and see if the fan stops cycling. If it does stop then the network is sending some signal that is prompting the printer to start the fan. The other possibility could be the temperature and / or humidity in the area of the machine, it could be close to being to hot and is cycling the fan to cool the machine down. If none of this helps please consider contacting your support centre for further assistance.
Thanks, CherylO-Xerox Community Manager
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