LG · Dryer
LG Dryer HS Error Code
Humidity sensor reading failed
What this error means
HS is a Humidity Sensor error on sensor-dry models. The board cannot read fabric moisture level, so automatic cycles may stop early or never advance from sensing mode.
How HS is detected
LG dryer models lock the door or lid before energizing fill, heat, or high-speed spin. HS means the latch switch never sent a "locked" signal to the main control, or the lock motor did not complete its travel. On LG DLEX4000W, LG DLE7300WE, and similar variants, clothing caught in the gasket, a misaligned strike, or a failed latch assembly are the most common mechanical causes—not the board itself.
Inspect the door gasket perimeter and strike alignment before replacing the latch. Fabric softener residue insulating the moisture bars is reported frequently on this code. After correcting mechanical issues, wipe the two metal moisture strips inside the drum with isopropyl alcohol and a soft cloth. If the latch clicks but HS persists, the door lock switch or wiring harness to the control board likely needs testing with a multimeter.
Do not force the door open during an active cycle; wait for the lock to release when the board de-energizes the lock motor—usually two to three minutes after canceling power on most LG units.
Common causes
- Fabric softener residue insulating the moisture bars
- Shorted sensor harness inside the drum bulkhead
- Corrosion on sensor contacts from chlorine bleach splash
- Control board humidity input failure
Step-by-step fixes
- 1Wipe the two metal moisture strips inside the drum with isopropyl alcohol and a soft cloth
- 2Avoid dryer sheets on loads when testing sensor dry after HS
- 3Run a Timed Dry cycle to confirm heat and tumble work independently of the sensor
- 4Retry Sensor Dry on a mixed load after cleaning the bars
When to call a technician
Replace the humidity sensor harness if HS returns immediately after cleaning the bars.
Affected models
- LG DLEX4000W
- LG DLE7300WE
- LG DLEX3900W
Prevention & maintenance
- Wipe the door gasket weekly and avoid overloading items against the seal—HS often starts as a slow leak or latch misalignment.
- Record when HS appears in the cycle and whether it clears after a 60-second power reset on your LG dryer—that detail speeds diagnosis if you call service.
- Keep the model and serial number from the rating plate when ordering parts for HS; LG uses multiple revisions with different harness lengths and board firmware.
- Photograph wiring connector orientation before disconnecting any component while troubleshooting HS; reversed plugs on pumps and valves cause immediate repeat faults.