LG Dryer d90 Error Code – Meaning, Causes & Fix

What Does d90 Mean?

What Causes This Error?

• Lint filter not cleaned regularly — the most common cause
• Lint accumulation inside the exhaust duct over months of use
• External vent cap on the outside wall partially blocked by lint, debris, or a pest nest
• Flexible exhaust duct kinked or crushed behind the dryer
• Exhaust duct exceeding maximum recommended length for the blower
• Dryer sheets or fabric softener residue coating and clogging the lint filter mesh
• Transition duct (flexible section from dryer to wall) clogged with dense lint buildup
• Exhaust duct partially disconnected inside the wall cavity, reducing effective diameter

How to Fix d90

1. 1

   Clean the lint filter. On LG dryers, the lint filter is located inside the door opening. Pull the filter straight up and out. Remove all lint by hand. To test if residue is clogging the mesh (from dryer sheets), hold the screen under running water — water should drip through freely. If water pools on the screen, lint filter mesh is clogged with softener residue. Wash the filter with warm water and a soft nylon brush under running water, rinse well, and allow to fully air dry before reinstalling.

2. 2

   Clean the exhaust duct. Pull the dryer away from the wall and disconnect the 4-inch exhaust duct from the dryer's rear port. Use a dryer vent cleaning brush kit (a flexible, rotating brush available at hardware stores) to push through the duct from the dryer end toward the exterior wall vent. Make several passes to dislodge all accumulated lint. Vacuum out loose lint from both ends of the duct. Reconnect the duct securely — use metal foil tape (not plastic tape) to seal the connection.

3. 3

   Check and clean the exterior vent cap. Go to the outside of your home and locate the dryer exhaust vent cap. It should have a hinged flap or louvers that open when the dryer is running. Confirm the flap opens freely and is not stuck, caked with lint, or blocked by a pest nest. Remove any blockage carefully using a brush or your hands. If the vent cap is heavily corroded or the flap is broken, replace it with a new vent cap.

4. 4

   Inspect the transition duct for kinks. The flexible duct section that connects the dryer's rear port to the rigid wall duct is the most commonly kinked section. With the dryer pulled out, look at this section carefully. Accordion-style flexible foil ducts are particularly prone to kinking and should ideally be replaced with semi-rigid metal duct, which maintains its shape and is less likely to accumulate lint. If kinked, straighten or replace the transition duct.

5. 5

   Run a diagnostic test cycle. After cleaning the filter, brushing the duct, and clearing the exterior vent, push the dryer back into position and run a full timed heat cycle (High Heat, 40 minutes) with a damp load of towels. At the end of the cycle, check if d90 is still displayed. If the code does not appear, the blockage has been cleared. If d90 still appears, try a second full duct cleaning pass as some lint deposits require multiple brush passes to fully dislodge.

6. 6

   Check if d90 advances to d80 or d95. If after cleaning, d90 advances to d80 or d95 instead of clearing, there is likely a more severe internal blockage or a partial exhaust duct disconnection inside the wall. In this case, a professional dryer vent cleaning service should be called to inspect and clean the full duct run with professional equipment.

When to Call a Professional

Can You Still Use the Device?

The LG dryer will continue to operate when d90 is displayed, but drying performance will be reduced and drying times will be longer than normal. You have 1–2 drying sessions to address the issue before it worsens. Do not ignore d90 — an unaddressed airflow blockage is a fire hazard.