Dishwasher Not Heating, Drying, or Sanitizing

Dishes that come out lukewarm, still wet, or with a film of undissolved detergent usually mean the water never reached the temperature the cycle called for — and that traces back to either the heating element itself or the sensor that tells the control board how hot the water actually is.

What this looks like

The cycle runs its full length and the door opens on schedule, but the dishes and the interior walls of the tub feel cool rather than hot, plastic items are still dripping instead of dry, and any sanitize-cycle indicator that's supposed to confirm a high-temp rinse never lights up. Sometimes there's an accompanying fault code; other times the cycle completes "successfully" with no code at all, just underwhelming results, because a mild heating shortfall doesn't always trip a full fault the way a completely dead element does.

Most likely causes, ranked

1. A failing or burned-out heating element. The most common root cause across every brand — elements corrode, crack, or simply wear out after years of cycles.
2. Mineral or limescale buildup from hard water. Scale coats the element and the temperature sensor alike, insulating the element so it works harder and reads inaccurately, and is worth ruling out with a dishwasher-safe descaler before assuming a part has failed.
3. A faulty temperature sensor or thermistor feeding the control board a reading that doesn't match reality, which can make a perfectly good heater look like it's failing.
4. Wiring or connector corrosion between the heater or sensor and the main control board.

Which error codes this can show as

• Bosch: E09 (open circuit in the heating element) and, on some models, E01 (a control-board fault that can point to the heating circuit depending on the specific model)
• Samsung: HE (heater or temperature detected incorrectly) and tE (temperature sensor reading out of range); on older rotary spray-arm Samsung models, 1E / IE can also flag an overheating condition from a stuck heating relay, distinct from its clogged-filter meaning on newer Waterwall models
• LG: HE (heater circuit fault) and tE (temperature sensor out of range)
• Whirlpool: F7E1 (heating element fault) and F3E1 (open temperature sensor circuit)

KitchenAid's documented codes in this dataset don't include a distinct heating-circuit or temperature-sensor fault. If a KitchenAid unit isn't heating or drying and the display isn't showing any of the codes listed on this site, the DIY checks below still apply — a persistent problem is a case for a technician even without a specific code to point to.

What you can check yourself

1. Power-cycle the dishwasher at the breaker for a few minutes and run a short cycle to rule out a one-off glitch
2. Run the kitchen hot water tap briefly before starting a cycle so the dishwasher fills with hot rather than cold water, which reduces the load on the element
3. Descale the interior with a dishwasher-safe descaler if you have hard water and haven't done this recently, since heavy scale affects both the heater and the temperature sensor
4. Access the sump area near the wash pump, if you're comfortable, and wipe any visible mineral film off an accessible sensor lens with a vinegar-dampened cloth

Related

• Dishwasher stuck or stopped mid-cycle
• Dishwasher blinking lights with no error code shown
• Bosch codes · Samsung codes · LG codes · Whirlpool codes · KitchenAid codes