LG · Dishwasher Serious

F31 — Heat-dry fan motor failure

On Dynamic Heat Dry models the dry-fan motor is not running when commanded. The wash cycle finishes but dishes will not dry properly.

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

How to fix it

  1. Note model number and order a Dynamic Heat Dry fan motor that matches it.
  2. Power off at breaker, remove the inner door panel screws, and locate the fan motor at the top of the door.
  3. Inspect blade for foreign material; rotate by hand — should spin freely.
  4. Test motor windings and connector continuity.
  5. Replace fan motor if open or seized.
  6. If a known-good motor still does not spin, replace the main PCB.
  7. Reassemble and run a Heavy cycle; verify fan audible during Dry phase.

Why it happens

Typical signs: F31 shown at end of cycle · Dishes wet after Dry phase · No fan noise during the drying portion · Cycle otherwise completes normally

  • Failed dry fan motor Burned winding or seized bearing in the dry blower.
  • Loose fan motor connector Harness backed out at the door or main PCB.
  • Obstructed fan housing Debris in the fan blade preventing rotation.
  • Main PCB driver fault Triac for fan output 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 fan motor Common replacement
    Amazon →

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 →

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.