Chosen Solution
When I turn the power on to my WF-3640 it starts beeping and flashing with message close cover then back to standby over and over never ending. I can shake it and it will work for a while then starts over. How do I access the sensor and clean it?
@fredric2 sounds like issues with the “Cover Open Sensor”. Should be on the front lip of the top cover and may require a partial disassembly. This may come in handy. You are looking for something like this (different model of the WF shown)
