Dishwasher Not Working ? Why will the dishwasher no longer start? There are various possible reasons why this might be happening, and these can be hydraulic, mechanical or electronic in nature. Discover how to quickly identify the cause of this failure to start in this article.
Dishwasher Won’t Start?
The water supply valve is not fully open
The water supply valve on your plumbing pipe might not be properly open. If this is the case, the water will flow into your dishwasher very slowly. Pay particular attention to self-tapping or quick fit valves. If these types of valves are not properly installed, the water will only trickle very slowly into your dishwasher. This will cause the wash programme to take several hours to complete. Your dishwasher may even not start at all.
The power supply is faulty
The source of the problem could be the plug socket or power supply. Check the condition of the plug and socket, and if they seem fine, check your fusebox to see if any of the fuses or circuit breakers have tripped. Also try unplugging your appliance from the mains for 20 minutes then plugging it back in. This can sometimes be enough to resolve the issue.
The start/stop switch is defective
If your appliance’s start/stop switch is defective, it will not allow your dishwasher to begin operating. You can check whether it’s working properly using a multimeter in ohmmeter mode. Disconnect the electrical connectors and place the multimeter’s two probes on the switch’s contacts with the switch in stop position. If it doesn’t have continuity, you will need to replace it.
The door safety latch is broken
The door safety latch ensures your dishwasher door closes securely. If the door catch is broken and doesn’t engage properly with the contact, or is defective, it will prevent your dishwasher from operating. You can check the contact using a multimeter in ohmmeter mode. Be careful when removing the front plate as it is very sharp.
The drain pump is blocked
The drain pump serves to evacuate the water from your dishwasher. If it’s blocked or faulty, the dishwasher will not operate. You can check the drain pump yourself; it can be found behind the access cover on the underside of the appliance. Be careful not to cut yourself: the sheet metal is sharp. Once you have accessed it, you can then dismantle and clean it.
The solenoid valve is blocked
The solenoid valve acts as an electric tap. If it’s defective or blocked, e.g. by sand, the dishwasher will not operate. Check the solenoid filter to see if it needs a quick clean. You can test the solenoid using a multimeter in ohmmeter mode. Its coil should give a reading of around 4 kilo ohms.
The pressure switch is defective
The pressure switch enables your dishwasher to control the level of water inside it. If it’s defective or fails to operate, it will send erroneous information to the circuit board and the appliance will not start. Most pressure switches are mechanical and can therefore be tested using a multimeter. Be aware, however, that the new electronically managed kinds of pressure switches cannot be tested using a multimeter.
The wash pump has failed
The wash pump (also known as a circulation pump) on your dishwasher enables water to be sprayed onto the crockery, cutlery, glasses and utensils, etc. If it’s blocked or defective, the appliance will not start and will also make a vibrating sound. You can dismantle it yourself to check to see if it’s blocked by a piece of glass or a pip from a piece of fruit. It can be found underneath the appliance; it will be the larger of the two pumps.
The water distributor is blocked
The water distributor, as its name suggests, distributes the water to the salt and ion-exchange resin compartment. If the water distributor is blocked due to limescale, the water will not be able to pass through and your dishwasher will fail to operate. You will, however, hear a humming sound from the solenoid valve as it tries to force the water through. When you remove the panels you’ll be able to see the tubes, which may look swollen.
The water softening unit is obstructed
The water softening unit serves to soften the water used to wash your crockery, cutlery, glasses and utensils, etc. The container can get blocked by limescale, or even accidentally if you happen to mistakenly put detergent in it instead of salt. If the wash cycle is launched under such circumstances, the container may get blocked and prevent the water from passing through at some stage in the cycle.
The anti-leak mechanism has been activated
The anti-leak mechanism on your dishwasher prevents the appliance from flooding. It can be found on the underside of the machine and usually consists of a float and a contact switch. If it is activated due to a leak, it will prevent your dishwasher from operating. Check to ensure there are no leaks by dismantling your machine.
The aquastop has been activated
An aquastop is a safety device located on the supply hose and housed in a box that screws onto the valve on your plumbing pipe. Aquastops usually work in tandem with the anti-leak safety mechanism and act by cutting off the water supply electrically. If this component is defective or activated due to a leak, for example, the appliance will not operate. Check to ensure there are no leaks by dismantling your machine.
The circuit board is defective
The circuit board controls all the various operating components of the appliance, one stage at a time. If the circuit board is defective, the appliance will not operate. You can either replace it yourself or call on the services of a manufacturer-certified technician.