LG · Dishwasher Serious

F35 — Heat-dry temperature sensing fault

On Dynamic Heat Dry models the temperatures of the heat-dry components cannot be measured. The fault usually points to the heat-dry heater, its thermistor, or harness.

Keep using it?
Limited use only
DIY difficulty
Hard
Verified against
lg.com ↗

How to fix it

  1. Power off at breaker and remove the inner door panel.
  2. Inspect the door-hinge harness — look for broken insulation or copper.
  3. Measure the heat-dry thermistor resistance per service-manual table.
  4. Measure the heat-dry heater for continuity; open = replace heater.
  5. Replace any failed component (thermistor, heater, or harness).
  6. If all door components test good, replace the main PCB.
  7. Reassemble and verify F35 does not return on next Heavy cycle.

Why it happens

Typical signs: F35 displayed during or after Dry phase · Dishes wet after cycle · Possible burning-plastic odor only if heater shorted · No audible heat-dry activation

  • Failed heat-dry thermistor Temperature sensor in the dry circuit open or shorted.
  • Failed heat-dry heater Heating element in the dry duct is open.
  • Broken / pinched harness in door hinge Wires routed through the hinge fatigue and break.
  • Main PCB sensor input damaged Sensor channel on board failed.

Parts you may need

If diagnosis points to a failed part, these are the common replacements. As an Amazon Associate we earn from qualifying purchases.

  • LG dishwasher heat-dry heater Common replacement
    Amazon →
  • LG dishwasher heat-dry thermistor Common replacement
    Amazon →

Related repair guides

Dishwasher Not Drying Dishes — How to Fix It →

More LG dishwasher codes

2H 2H — Delay-start indicator (2 hours remaining) AE AE — Leak Detected (Aqua Error) bE bE — Bubble / oversuds error CE CE — Motor / communication error CL CL — Child lock / control lock active CR CR — Test / calibration mode

All LG codes → All dishwasher codes →

Frequently asked questions

What does the F35 code mean on a LG dishwasher?

On Dynamic Heat Dry models the temperatures of the heat-dry components cannot be measured. The fault usually points to the heat-dry heater, its thermistor, or harness.

What causes the F35 code on a LG dishwasher?

Failed heat-dry thermistor: Temperature sensor in the dry circuit open or shorted. Failed heat-dry heater: Heating element in the dry duct is open. Broken / pinched harness in door hinge: Wires routed through the hinge fatigue and break.

Is it safe to keep using a LG dishwasher with a F35 error?

Limited use only. This is rated a serious-severity fault.

How do I fix F35 on a LG dishwasher?

Power off at breaker and remove the inner door panel. Inspect the door-hinge harness — look for broken insulation or copper. Measure the heat-dry thermistor resistance per service-manual table.

Always unplug an appliance before servicing it. This guide is for informational purposes and is not a substitute for a qualified technician. Verified against manufacturer documentation: lg.com.