My machine is a SANYO ASW F101AT when I start the machine the water over fills and shows an ER. there must be level switch some where, How do I fix it

There is a water level switch and it is controlled by a small tube from the tub to the switch
as the water rises in the tub , the pressure in the tube over comes a spring tension in the switch that you set by wash load level
when that setting is overcome the switch powers the solenoid for the water inlet and shuts it off at the same time starting the wash cycle
so you have 2 possible problems
i--- level switch
or
most likely a problem water control solenoid or diaphragm in the solenoid
the fix for the solenoid is a new one
check the tube to the switch or check the switch
do that bu setting low water level and listening for a solenoid operation for the water