F7 occurs when there is a flow meter issue. The device is located in the left-hand part of the machine and looks like a plastic tank.
To clear the error, please, do the following:
Disconnect the power.
Put the dishwasher in a place where you can work on it conveniently.
Remove the top (in free standing dishwashers).
Remove the left-hand panel.
Open the flow meter (the plastic tank, as described above).
Pull the small plug off and on several times to clean the connection.
Try a cycle again.
If it does not work, address a technical support service.
Other Whirlpool dishwasher error code: