When a Thermador dishwasher won’t start, the cause is almost always the door not registering as closed, a power or breaker problem, a cycle that was never confirmed with Start, or a safety stop such as water in the base pan. Close the door firmly until it clicks, check the breaker, choose a cycle and press Start, and if nothing changes, switch the breaker off for two minutes and try again. A dishwasher that stays dead after that needs a technician, not more button pressing.
Why won’t my Thermador dishwasher start?
Dishwashers will not run unless several conditions are met at once: power at the unit, a closed and latched door, a selected cycle that has been confirmed, and nothing in the control logic that says something is unsafe. When any one fails, the machine simply sits there. That is why the same symptom has five or six different causes, and why the right approach is to work through the cheap, safe checks first, in the order below, rather than guessing at the part.
Before you start, keep in mind that a dishwasher is a water appliance with a high-voltage supply. Switch the breaker off before you reach behind or under the machine, and never remove panels or touch wiring while the power is on.
Is the door closing and latching?
Open the door fully and close it with a firm push until you hear the latch click. Dishes or a rack sticking out of the tub, the lower rack not pushed in or a spray arm blocked by a utensil can all stop the door from closing completely. Look at the latch on the door and the strike in the tub for food, a broken tab or a bent part. If the display shows the E06 door switch code, the control believes the door opened during the cycle, and our Thermador dishwasher E06 page explains what to check.
Is the dishwasher getting power?
A completely dark display means no power reaches the control. Check the breaker in your panel and, if the dishwasher is plugged in under the sink, confirm the plug is seated and the outlet or switch feeding it is on. Do not use a cheater cord or an adapter. If the breaker trips as soon as you switch it on, leave it off and call, because that points to a short or a leak. If the breaker is fine and the machine is still dark, the control board or its fuse may have failed; the E01 communication code is one of the clues, and our E01 page describes it.
Is a setting stopping it from starting?
With the display lit and the door closed, check for a delay start that is counting down, a control lock or child lock that blocks the panel and a cycle that was selected but never started. Many panels need you to press Start after choosing a cycle, and some need the door closed within a few seconds of pressing it. Cancel any pending program by holding the cancel or reset control for a few seconds, as your manual describes, choose a cycle again and press Start. Our guide to Thermador dishwasher troubleshooting lists the panel behaviors for the common models.
Could the water supply or a safety sensor be the reason?
A dishwasher that starts and then stops soon after may be waiting for water. Make sure the supply valve under the sink is fully open and the water supply line is not kinked. A fill problem produces codes such as E04 or E05, and an overfill produces E17. A different kind of stop is the anti-flood sensor: if water sits in the base pan, the dishwasher shuts the cycle down to protect the floor, and the E15 code appears. If you see E15, do not keep restarting the machine. Switch it off, look for water under it and read our E15 page before you run another cycle.
How do you reset a Thermador dishwasher?
- Cancel the cycle from the panel as the manual describes, and open the door to drain any standing water if the cycle was running.
- Switch off the breaker for the dishwasher and leave it off for two minutes. This clears many temporary control faults.
- Switch the breaker back on, close the door firmly, choose a cycle and press Start.
- Watch the first minutes. You should hear the water valve and then the pump.
If the same fault returns right away, a reset will not fix it, and repeating the reset only delays the diagnosis. Our Thermador dishwasher error codes guide lists the common codes in one place.
When should you call a technician?
Call when the breaker trips, when water is in the base pan, when the display is dead after the power checks, when the same code keeps coming back or when you can smell burning. A diagnosis is far cheaper than a flooded kitchen or a burned control. Write down the code, what the display showed and when it last ran normally, because that short history lets a technician arrive with the right part instead of making a second trip. Our Thermador dishwasher repair page explains how a visit works.
