Quick answer
If your dishwasher won't run, first check the power and door latch. Ensure the water supply is on and the drain is clear. If these don't work, test the float switch or control board.
Confirm the symptom
- Dishwasher won't start when you press the start button
- No power indicator lights are on
- Door closes but the cycle doesn't begin
Tools and prep
- Screwdriver set
- Multimeter
- Flashlight
- Plumber's putty
- Rubber gloves
- Turn off power at the circuit breaker
- Shut off water supply to the dishwasher
Step-by-step troubleshooting
- Check Power SupplyDo: Verify the circuit breaker hasn't tripped and the outlet has power.Observe: Breaker is on, outlet works with other devices.Means: Power is available.Next: Check the door latch.
- Check Door LatchDo: Inspect the door latch for damage or misalignment.Observe: Latch engages fully and clicks into place.Means: Door is properly latched.Next: Test the float switch.
- Test the Float SwitchDo: Lift the float switch to see if the dishwasher starts.Observe: Dishwasher starts when float is lifted.Means: Float switch is faulty.Next: Replace the float switch.
- Inspect the Water SupplyDo: Check the water valve and ensure the supply line is open.Observe: Water flows freely from the supply line.Means: Water supply is adequate.Next: Check the drain system.
- Check the Drain SystemDo: Ensure the drain hose isn't clogged and the air gap is clear.Observe: Drain hose is clear and air gap functions properly.Means: Drain system is unobstructed.Next: Test the control board.
- Test the Control BoardDo: Use a multimeter to check for continuity on the control board.Observe: No continuity or error codes appear.Means: Control board is faulty.Next: Replace the control board.
Common causes
| Cause | Likelihood | Difficulty | Part often needed |
|---|---|---|---|
| Tripped Circuit Breaker Power interruption due to overload or short circuit. | Common | Easy | None |
| Faulty Door Latch Door doesn't close properly, preventing the cycle from starting. | Common | Easy–Medium | Door latch assembly |
| Clogged Drain Water can't drain, causing the dishwasher to stop or not start. | Common | Easy | Drain hose or air gap |
| Malfunctioning Float Switch Float switch thinks the dishwasher is full, preventing the cycle. | Sometimes | Easy | Float switch |
| Water Supply Issue No water entering the dishwasher due to a closed valve or clogged filter. | Sometimes | Easy | Water inlet valve |
| Faulty Control Board Control board not sending signals to start the cycle. | Rare | Hard | Control board |
Parts matching
Common parts needed for a dishwasher not running include:
- Door latch assembly
- Float switch
- Water inlet valve
- Control board
- Drain hose or air gap
Purchase parts specific to your dishwasher model for compatibility.
When to call a professional
- Dishwasher still doesn't run after replacing all common parts
- You're unsure about electrical components or control board replacement
- You notice water leakage or electrical burning smells
- The dishwasher is under warranty and you don't want to risk voiding it
FAQ
Why won't my dishwasher start even though it's plugged in?
Check the circuit breaker and door latch. A tripped breaker or faulty latch can prevent the dishwasher from starting despite being plugged in.
How do I know if the float switch is bad?
If the float switch is stuck or doesn't allow the dishwasher to start when lifted, it's likely faulty and needs replacement.
Can a clogged drain prevent the dishwasher from running?
Yes, a clogged drain can stop the dishwasher from starting or cause it to stop mid-cycle. Clear the drain hose and air gap to resolve this.
Is it worth replacing a control board?
Replacing a control board can be costly. Consider the age and value of your dishwasher before deciding. If it's older, a new unit might be more cost-effective.