LG Dryer Error Code d90

LG Dryer Error Code: d90 — What It Means and How It Affects You

The LG dryer error code “d90” is a less-common diagnostic indicator that can point to problems related to drying performance, sensor/communication faults, or ventilation and overheating conditions. Exact meanings vary by model and firmware, but users typically report issues such as longer drying times, intermittent stops, garments that remain damp, or the dryer entering a protective shutdown. In some cases a d90 can indicate a sensor reporting unexpected values (moisture/thermistor), a control/communication glitch, or airflow/heating problems that trigger safety limits. The practical impacts on users include wasted energy, repeated cycles, potential fabric damage from over-drying if controls behave erratically, and in extreme cases an increased fire risk if vents are clogged and heat builds up.

Common Causes

• Clogged lint trap or venting — restricted airflow raises temperatures and lengthens drying time.
• Dirty or failing moisture sensor — gives incorrect moisture readings and prevents cycle completion.
• Faulty thermistor or temperature sensor — causes improper heat regulation and safety shutdowns.
• Overheating / tripped thermal fuse or thermostat — safety components shutting off heat or the motor.
• Blower wheel or motor problems — reduced air movement causing poor drying and error states.
• Control board (PCB) or software/firmware glitch — intermittent or persistent error codes and communication failures.
• Loose or damaged wiring / connectors — intermittent sensor or heater/power failures.
• Door switch or latch fault — dryer may not register a proper closed door, inhibiting operation.
• External conditions — excessively long vent runs, crushed ducts, or backdraft dampers causing poor exhaust.

Troubleshooting Steps

1. Power cycle the dryer: unplug or switch off the breaker for 1–2 minutes and restart. This can clear transient electronic glitches.
2. Check your manual/model code list: confirm whether LG documents a specific meaning for d90 on your exact model — meanings sometimes differ across models and years.
3. Inspect and clean the lint trap: remove lint, vacuum out the trap housing, and run a quick cycle to see if the error clears.
4. Examine the exhaust vent and ductwork: disconnect the vent and check for lint buildup, kinks, or obstructions; clean the duct to the exterior vent cap.
5. Run a self-diagnostic test (if available): many LG dryers have a diagnostic mode that shows detailed error codes and helps narrow faulty components — consult your manual for entry steps.
6. Clean the moisture sensors: wipe the metal bars inside the drum with a soft cloth and rubbing alcohol to remove residue that can fool sensors.
7. Check the door switch and latch: ensure the door closes securely and the switch actuates; replace if loose or non-responsive.
8. Inspect heating and safety components: if you are comfortable and the dryer is unplugged, check the thermal fuse, heating element, and thermostats for continuity with a multimeter.
9. Verify motor and blower wheel operation: listen for unusual noises, reduced suction, or mechanical resistance—replace worn parts as needed.
10. Examine wiring and connections to sensors and the main control board: look for burnt connectors, pinched wires or corrosion and reseat connections.
11. Update firmware or reset control board (if available): some models allow firmware updates or extended resets—refer to LG support or authorized service guidance.
12. When in doubt, call a qualified technician: if troubleshooting above does not clear the d90 code or you encounter electric/gas components, hire a certified appliance technician to diagnose and repair.

Maintenance / Prevention Tips

• Clean the lint filter after every load to maintain airflow.
• Vacuum the lint trap housing monthly to remove hidden lint buildup.
• Inspect and clean the external dryer vent and cap every 3–6 months.
• Use smooth, short, rigid or semi-rigid ducting rather than flexible foil to reduce lint accumulation.
• Keep the dryer area clear of dust and lint buildup around the machine.
• Wash or wipe moisture sensor bars with rubbing alcohol every few months to prevent residue buildup.
• Do not overload the dryer; allow adequate tumbling and airflow per load size.
• Replace long, circuitous vent runs with a more direct route to the exterior when possible.
• Check the vent hood flap regularly to ensure it opens freely and is not blocked by debris or animal nests.
• Schedule professional vent cleaning annually if you use the dryer heavily or have long ducts.
• Replace worn door gaskets or latches to ensure a proper seal and operation.
• Address unusual noises or vibrations promptly to avoid secondary damage to the blower or motor.
• Keep the dryer level to prevent excess wear on bearings and belts.
• Follow manufacturer recommendations for cycle selection and load size to reduce strain on sensors and heating components.
• Use garment bags for items that shed lint heavily to reduce lint migration to sensors and ducts.
• Consider periodic inspection of internal components (motor, blower, heating element) by a technician if the unit is older.

FAQs

Conclusion / Safety Notice

Your safety is the priority. Always unplug the dryer (or switch off the breaker) before opening panels or handling electrical components. Gas dryers require additional caution — shut off the gas supply and contact a qualified technician for any gas-line work. If you are unfamiliar with electrical testing or cannot isolate the fault through cleaning and basic checks, stop and call a certified appliance repair technician. Attempting complex repairs without proper training can risk electric shock, gas leaks, or fire.

If the d90 code persists after cleaning lint traps and vents and running basic diagnostics, contact LG support or a licensed appliance technician. Professional diagnosis ensures correct parts are replaced and safety systems remain intact. Regular maintenance helps prevent many common causes and keeps your dryer operating efficiently and safely.