Your dishwasher heats water as high as 140 degrees Fahrenheit in its lower basin (the area below the bottom rack) with a metal heating element. Spray arms pump that water over the dishes while dispensing the detergent. After a second rinsing spray, the heating element kicks in again to dry the dishes. High temperature and water pressure mean that the door and other potential escape points must remain perfectly sealed.
For all repairs that involve removing the machine from its location, follow these procedures. Dishwashers are top-heavy, so there is the danger of them falling forward after they have been removed from the bay.
Most dishwasher issues center around those basic, core functions and require only simple tools and basic skills to fix problems.
How to Fix an Overflowing Dishwasher
Located in the dishwasher basin, the float assembly is a saucer-shaped device that floats up as water rises in the basin. When the water reaches a certain height, the attached overfill float switch signals the dishwasher to cut off the water. If the float is not moving or the switch is not working, the water will keep rising until it overflows.
Fix the Float
Raise and lower the float a few times by hand to "unstick" it. The float needs to move freely to activate the switch. If this is not happening or if the float is visibly damaged, replace the entire float assembly.
Check the Overfill Float Switch
The float switch is a small relay switch that allows or cuts off a low-voltage electrical current. Lift the float and listen carefully. If you hear a hard metallic click, there is a good chance that the switch itself is working correctly. If not, replace this inexpensive part.
Replace the Overfill Float Switch
After performing shut-down procedures, locate the switch. Unsnap the old switch, which should be very easy, and snap the new switch into the proper place.