LG Dryer D90 Error Fix, Step-by-Step Troubleshooting Guide

November 30, 2025 Austin Jones Dryer Error Codes

Introduction: Why the D90 error matters and what you will learn

If your dryer just flashed D90, you want a fast, reliable lg dryer d90 error fix, not guesswork. This code most often points to an overheating or ventilation issue, for example a clogged vent, full lint trap, or restricted airflow causing the dryer to shut itself down for safety.

Here is what you will learn, step by step. First try a quick reset and basic checks, such as removing lint from the screen and emptying the vent tube. Next measure airflow at the exhaust, inspect the thermal sensor and high limit thermostat, and look for motor or control board faults if overheating persists. Finally I will show when to call a technician, and what parts and tools to have ready for a fast repair.

Quick overview: What the LG D90 error code means

If your dryer displays the D90 error, it usually means the machine is detecting a problem in the drying circuit, most often caused by airflow or sensing failures. Common real world causes include a clogged lint trap or outside vent, a faulty moisture sensor or thermistor, an overloaded drum that prevents proper tumbling, or an intermittent control board fault. You might see the error when the dryer stops mid cycle, fails to heat, or keeps cycling without finishing.

If you searched for lg dryer d90 error fix, start with simple checks: clean the lint screen, inspect the exterior vent for blockages, reduce the load size, and power cycle the unit. If the error persists, the issue likely needs sensor or board diagnosis.

Safety first and tools you need

Before you start any lg dryer d90 error fix, cut power and confirm it’s dead. Unplug the dryer, flip the breaker off, then use a multimeter to confirm no voltage at the terminal block. Let the drum cool, wear insulated gloves and eye protection, and clear lint from the trap and vent. Have these tools: multimeter, Philips and nut driver sets, needle nose pliers, vacuum, putty knife. Stock replacement parts like a thermal fuse, door switch, moisture sensor, and control board.

Step 1, power cycle and reset to rule out a glitch

Before digging into parts, do a simple power cycle. It often solves the D90 error because the control board or sensors are stuck in a transient state. Here is a safe, step by step method.

  1. Turn the dryer off using the power button, then unplug it from the wall outlet. If the outlet is hard to reach, switch the circuit breaker off instead.
  2. Wait five to ten minutes. This lets internal capacitors discharge and clears stored error codes.
  3. Plug the unit back in or restore breaker power, then run a quick 10 minute hot or timed dry cycle to see if the D90 error returns.

Some LG models support a factory reset from the control panel. Check your owner manual for the exact sequence, or contact LG support. If the error persists after a full power cycle and factory reset, move to sensor and control board troubleshooting.

Step 2, inspect lint filter and exhaust venting

Clogged lint traps and blocked vents starve the dryer of airflow, which raises internal temps and can trigger error codes. Start simple, remove the lint screen, peel off the trapped lint, then run a flashlight down the intake slot to spot deeper buildup. If you see a cake of lint, vacuum it with a narrow nozzle or use a dryer vent brush to pull debris out.

Next check the exhaust duct to the outside. Disconnect the flexible duct and shine a light through it, then push a long brush all the way to the exterior hood and sweep out lint. While the duct is disconnected, turn the dryer on for a few seconds to blow remaining dust into a trash bag, after you stand back.

Inspect the outside vent flap for obstructions, and test airflow by holding a tissue near the outlet while the dryer runs; weak suction means a partial blockage. For persistent problems, replace old accordion ducting with rigid or semi rigid duct, and schedule professional vent cleaning yearly. These steps are essential for an effective lg dryer d90 error fix.

Step 3, clean and test the moisture sensor

The moisture sensor lives inside the drum, just above the lint trap. It looks like two thin metal bars. To fix the LG dryer D90 error, start by unplugging the dryer and pulling out the lint screen so you can see the sensor clearly.

  1. Clean it: dampen a soft cloth with white vinegar or a baking soda paste, scrub both bars until shiny, then wipe dry. Grease, fabric softener residue, and corrosion are the usual culprits.

  2. Test it quickly: reconnect power, toss in a damp towel, and run a short sensing cycle. The dryer should detect moisture and continue running. If you have a multimeter, power down, probe the two terminals, then wet the bars with a little water. The resistance should drop noticeably when wet. If resistance stays the same or reads open, the sensor or its connector is faulty.

Also check the wiring plug for corrosion. Cleaning often fixes the D90 error, otherwise replace the sensor assembly.

Step 4, check door switch and drum seals

A faulty door switch or worn drum seal can mimic the symptoms tied to an lg dryer d90 error fix, because the machine may think the door is open or lose proper air flow. That causes the dryer to refuse to start, stop mid cycle, or run without heating effectively, and it can trigger an error code or the door ajar indicator.

Quick test for the door switch, no guesswork: unplug the dryer, open the door, find the small plastic switch on the frame, unplug its wiring harness, set a multimeter to continuity or ohms, press the switch. You should get continuity when pressed, and no continuity when released. No continuity means replace the switch.

Seal checks you can do fast: inspect the drum gasket for tears, flattening, or lint buildup; run a flashlight around the closed door to spot light leaks; spin the drum by hand to feel rubbing or gaps. If the seal is cracked or loose, replace it to restore proper operation.

Step 5, test thermal fuse, thermostat and heating components

Start by unplugging the dryer and removing the rear panel. Locate the thermal fuse on the blower housing and the cycling and high limit thermostats on the exhaust path and heater assembly. Set a multimeter to continuity or low ohms, touch probes to the two terminals, and listen for a beep or look for a near zero reading. A failed thermal fuse or thermostat will show open circuit, no beep, or infinite resistance.

Check the heating element by measuring continuity between its two terminals, and then from each terminal to the metal chassis to detect a ground short. The element should show continuity but not a short to ground.

Signs the D90 code is caused by heating failure include the drum tumbling without heat, very long dry times, and D90 appearing after several cycles. Replace any open fuse or thermostat, replace the element if it has no continuity or is grounded, and consider replacing both thermostat and thermal fuse together for a reliable lg dryer d90 error fix.

How to test after each fix and what results mean

After each repair step, run a short, repeatable test so you know if the lg dryer d90 error fix worked. Simple plan, do this after reconnecting power and securing parts: 1) Start a 10 minute timed dry, 2) Watch the display for the D90 code during the first two minutes and again at cycle end, 3) Confirm the drum tumbles and the unit heats or the sensor cycle behaves normally. If the code disappears immediately and does not return on three consecutive tests, the repair is confirmed. If the code returns within two minutes, suspect wiring or control board issues and proceed to the next troubleshooting step. Log results and take photos.

When to call a professional or order replacement parts

If the D90 error keeps returning after you try basic resets, cleaning the moisture sensor, and checking vents, call a pro. Also stop DIY if you smell burning, the drum will not spin, or the dryer has electrical issues. For quick troubleshooting success, attempt the lg dryer d90 error fix steps first, but do not force parts you cannot test.

Common parts to order, confirm compatibility with your exact model number:

  1. Thermal fuse or thermistor
  2. Moisture sensor assembly
  3. Heating element or heater relay
  4. Drum belt or idler pulley
  5. Main control board

When talking to a technician, get a written estimate, ask for the failed part to be shown, request OEM parts only if possible, and confirm warranty on labor and parts before work begins.

Preventive maintenance to avoid future D90 errors

Clean the lint trap after every load, and wipe the housing monthly with a vacuum or microfiber towel. Deep clean the vent and duct every 3 to 6 months, more often if you run heavy loads. Swap flexible foil duct for rigid or semi rigid metal, and check the exterior vent cap for blockages or pests monthly. Clean moisture sensors once a month with isopropyl alcohol so the dryer reads properly. Avoid overloading, and run a high heat cycle with an empty load and a damp towel quarterly to force out residual lint. These habits make an lg dryer d90 error fix far less likely.

Conclusion and final troubleshooting checklist

Quick recap: for an lg dryer d90 error fix start with a power reset, clean the lint trap and exhaust vent, verify the door switch and latch, inspect sensor and thermistor connections. Checklist:

  1. Reset power.
  2. Clean lint screen and vent.
  3. Check door switch, wiring, connectors.
  4. Replace suspect sensor or thermistor.
  5. Call LG service if error persists.
    Work safely, unplug before testing, use OEM parts, and call a pro when wiring or gas components are involved.