I have an F4 (drainage) fault on my whirlpool 6th Sense dishwasher.
All research has suggested drainage blockage or drainage pump or pressure switch. I've eliminated blockage and the pump is Ok.
I tried to locate a pressure switch but not found one, but instead located an optical water level sensor switch. I do not know how to test this switch,
and if it is faulty that this could cause the F4 problem.
Any advice would be appreciated. Thanks.
