How to Repair Dish Washers

Modern dishwasher maintenance and repair can seem like a daunting do-it-yourself project. The good news is that most of them still operate the way they did 20 or 30 years ago. Once you get past the controls, the remainder of the dishwasher is much less intimidating. If you have a knack for tinkering, you may be able to diagnose the problem and repair it yourself. You just need the right tools and a good sense of the dishwasher's various components.

Things You'll Need

• Screwdriver VOM set to the RX1 scale

Instructions

1. Perform some basic troubleshooting--the problem with the dishwasher may have nothing to do with its innards. Check the outlet to make sure it is receiving power, make sure the water supply is clear, and check during a cycle to see that the water is hot enough. Pay close attention to the door latch too. Most dishwashers won't work unless the door is securely closed.

2. Unplug the dishwasher and shut off the water supply. You don't want either water or electricity running through it while you are tinkering.

3. Remove the retaining screws on the control panel of the door, which will give you access to the dishwasher's inner components. They are usually hidden by plastic molding, which can be pried off safely with a screwdriver. In some cases, you'll have to take the entire door panel off instead of just the control panel.

4. Check the door gasket. This is likely the culprit if the dishwasher is leaking. When gaskets wear out, they tend to harden and crack, which creates an imperfect seal. If the gasket isn't in need of replacement, check to make sure it forms a tight seal with the door. You may need to tighten or loosen the retaining bolts to refit it.

5. Check the latch to make sure the door can close securely. It may have loosened or moved out of alignment, in which case you can adjust it with a screwdriver by tightening or loosening the bolts.

6. Take off the panel that covers the door switch and remove one of the lead wires. Connect it to a VOM set to the RX1 scale, then close the door. If the VOM reads zero, the door switch is working. Otherwise, it will need to be replaced. The door switch controls the timer and similar components: If it's broken, the dishwasher will not start.

7. Remove the bottom rack and check the float switch. This keeps the dishwasher from overflowing with water. You may need to dislodge it or remove food particles that have caused it to become jammed. If it is worn out, it will need to be replaced. Test it with a VOM as well. If the meter reads higher than zero, the switch is broken and you will need a replacement.

8. Test the dishwasher timer with a VOM. Again, if it reads higher than zero, then it needs replacing.

9. Check the inlet valve for any damage or obstruction. The screens may be clogged with minerals, in which case they can be removed and rinsed out. A worn-out valve can be removed by unscrewing it from the mounting bracket and replacing it with a new one. If the valve is controlled by a solenoid, disconnect a wire and connect it to the VOM. In this case, the meter should read anywhere from 100 to 1000 ohms. If the reading is any higher, you should replace the solenoid.

10. Check the heater with a VOM. It should rank between 15 and 30 ohms. If it doesn't, then disconnect the leads from the terminal screws and unscrew the remainder of the heater from its housing. You can then remove it through the tub and replace it with a new heater.

11. Remove the strainer and spraying arms from the dishwasher and check them for any food build-up or mineral deposits. Clean them thoroughly with water before replacing them.

12. Remove the sprayer arm to check the water pump beneath. Once you've unscrewed the central bolt, you should be able to remove the components one at a time. Make sure you keep track of the order they are in so you can replace them properly when you are done.

13. Clean the lower pump impeller if it is clogged. If that doesn't work, then the pump should be serviced by a professional handyman.

14. Reattach the control panel on the door when you have finished repairing the faulty component.