So you’ve inserted a dishwasher tablet, closed the door and switched it on, but your dishwasher doesn’t start? The most common reasons a dishwasher won’t turn on are problems with the power source, a faulty door latch or an issue with the electronic controls.
But before calling a service person, try a few troubleshooting tips.
Note that some of these steps require opening up the dishwasher. If you are uncomfortable doing it or you are afraid you might damage something, let a professional handle it.
What Do You Do When Your Dishwasher Won’t Turn On
A. Tools You’ll Need
- Multimeter electrical tester
- Nut driver
- Masking tape and pen
B. Power Source
Make sure your washer is properly plugged into the electrical outlet. Check that the breaker switch on the mains is turned on. Also ensure that the electrical box, fuses, and circuit breaker are in good working condition. You might need to replace them if they are blown.
Note: Never use extension cords to power your dishwasher. The power cord will overheat, causing your cord and anything surrounding the cord to melt. This can cause a fire or damage your dishwasher.
C. Door Latch
Your dishwasher door has a latch that will not let the controls operate if the door is not properly closed. If the latch is faulty, then the dishwasher will not start.
Some latches also control the water inlet valve. If the latch is bad, the washer will not fill with water.
The latch is located on the upper side of the door panel. There is a pin or switch attached to the lid. This switch (when door is closed) will supply power to the controls.
If your washer will not start, make sure the switch is working. If the door closes properly but no power is being supplied to the washer’s controls, then the switch is most likely bad.
Check the switch for continuity using a multimeter. Remember to turn off power to washer and carefully examine the door latch.
If there is no continuity, you’ll need to have the switch replaced.
D. Loose or Faulty Timer
The timer in your dishwasher controls electro-mechanical components of the washer. These include the heating element, water inlet valve, drain pump, and wash pump.
This timer is turned on by pulling out or rotating the timer knob. Sometimes the knob wears out and can’t properly engage the timer shaft. When the worn out knob slips, your washer won’t start.
If, after pulling or rotating the timer knob, your washer doesn’t start, test it for continuity with a multimeter.
Turn off power supply to the dishwasher and inspect the timer knob. Make sure the timer shaft engages the knob when it is pulled or rotated. If there is no continuity, replace the knob.
E. Thermal Fuse/Cut Out Defects
The thermal fuse protects your dishwasher from overheating. If there is a problem with the thermal fuse, the dishwasher will not receive power.
To locate it, you’ll have to remove the inner door of the washer after unplugging it. The thermal fuse is connected to the circuit board by two wires.
Disconnect the two wires and check the continuity of the thermal fuse using a multimeter. If no continuity is observed, replace the thermal fuse or cut out.
F. Motor Start Relay
The motor start relay, as the name suggests relays the “start command” signal to the motor.
If the start relay has malfunctioned, the start signal won’t get relayed to the motor of your dishwasher.
To test the start relay, use a multimeter to check for continuity. Disconnect power and locate the start relay next to the pump or motor. Test the coil portion of the relay for continuity. Replace the unit with a new one if it is faulty.
G. Drive Motor
The drive motor is responsible for water circulation inside your dishwasher. It receives a start signal from the start relay.
If the motor makes strange humming noises or doesn’t turn on, then it might be faulty.
To test if the motor works, remove the belts and try to start the motor. If it runs then you know something else in the washer is causing the issue.
If the direct drive motor won’t start then it should be replaced.
H. Control Board/Control Panel
The control board controls all component of your dishwasher. If it doesn’t properly control the door lock, motor, filling valve, drive motor or drain motor, your washer won’t start.
The only way to verify if the control board has malfunctioned is to visually inspect it.
Check for burned areas or any component on the board that may look burned or has loose connection. Tighten any loose connections and replace the burned components.
I. Extra Tips
- Always unplug your washer from power source before you inspect it. Continuity tests don’t need to have current running through the circuit so there’s no need to keep the power on.
- Make sure you disengage the child lock safety feature of your dishwasher before you run it. Check for instructions in the manufacturer’s user manual.
- Label all connecting wires when inspecting (Use masking tape and a pen). This will help you place them back correctly.
- Make sure that all replacement parts are certified and verified for authenticity.
If your washer won’t start despite your attempt to troubleshoot these issues, there’s a good chance there is a major problem. You’ll need to consult an authorised expert who can safely open up your dishwasher and determine if a repair or replacement is needed.
Call the manufacturer for advice on how to get your dishwasher diagnosed and repaired.