Symptom diagnosis starts below. But first…
Are you a “gearhead?”
I tried to write this guide to help everyone, even beginners, who wants to try to fix their own dishwasher.
But of course, not everybody has the same skill set. Some people are VERY mechanically-savvy, And some have very few mechanical skills and little knowledge.
So please let me ask you a couple of quick questions, to separate the novices from the “gearheads…”
Do you know basically how a dishwasher operates?
For example, do you know that a wash always begins with a DRAIN cycle?
Do you know what a solenoid valve is?
If you know all these things, then click below to start diagnosing.
If you don’t know these things, you really need to.
Do you know how to use a Multimeter to test voltage, continuity and resistance? You might need to. If you don’t, there are instruction links on pages where you need to know.
Diagnosing a dishwasher can be tricky.
The same malfunction can cause different symptoms.
Heavy spotting and filming or etching of the dishes (poor wash quality) can be caused by many different conditions and malfunctions.
So let’s start with YOUR dishwasher…what are the complaints/symptoms?
Spotting or Filming is water spots, or a whitish or grayish film left on the clear glassware at the end of a wash.
Etching of your glassware is damage of a more permanent nature. In early stages, the glassware may have an iridescent blue, pink or purplish look when you hold it under the light in a certain way. In later stages, the glass takes on a cloudy or milky appearance, or it may even be pitted. These cannot be removed by any amount of scrubbing.
Food Left on Dishes: at the end of a wash, little bits of food are left sticking to dishes
Darkening or Blackening of Silverware is a grayish discoloration of silverware at the end of a wash.
A groaning sound while the motor is running, during wash and rinse cycles, is usually deteriorated pump or motor bearings. See Pump and Motor Service.
A high-pitched rattling noise during a wash or rinse cycle is usually caused by bits of broken glass or rust getting into the pump impeller or spray arms. It is also frequently caused by worn out bearings in the pump or electric motor.
There are instructions on how to remove spray arms on the Water Filter Cleaning page.
Try removing the spray arms and clearing them of debris. Poke a toothpick through the holes and try to dislodge whatever is clogging them, then fill the spray arm and shake it before draining the water out of the center hole.
Cleaning the spray arms can be difficult…sometimes it’s easier just to replace them.
If your dishwasher has lights, but is doing nothing else, make sure your door is fully closed and latched. It sounds crazy, but I have “fixed” a lot of dishwashers for a lot of people just by doing that.
The problem could also be the door switch itself. Remove the door panel and test the switch as described in Electrical Testing.
There is a possibility that your timer is faulty. Click here for repair information.
If your dishwasher is doing nothing, no lights, no noise, nothing:
I hate to insult your intelligence, but…you’ve checked the breaker, of course, right?
And made sure it’s plugged into the wall?
Here is something you may NOT have thought of…make sure you plug the power cord back into the correct receptacle. Most dishwashers are plugged into a receptacle under the sink…into the same wall outlet as the garbage disposal. The garbage disposal receptacle has a wall switch…if you plug the dishwasher into the wrong receptacle, your dishwasher may not work unless the wall switch is on!
There is one more place to check…the incoming junction box. Power coming from the house is usually routed into this box, and connected to the dishwasher’s wiring using wire nuts. Sometimes they can vibrate loose and wires will short. This will probably trip your breaker…but when you reset it, you will still have no power. The wires inside the junction box are burned.
Though some are hard-wired into the wall, most dishwashers are plugged into a regular outlet beneath the kitchen sink. If you are unlucky enough to have one that’s hard-wired, you must shut off the breaker and disconnect the main power cord at the junction box. This box is usually located just inside the kickplate on the front corner of the machine