Samsung Dryer Won't Stop Running: Sensor and Relay Fixes
Quick Answer
Check if Wrinkle Prevent is active first because it tumbles intermittently after the cycle ends and is not a malfunction. If the dryer truly will not stop, clean the moisture sensor bars inside the drum to remove fabric softener residue.
Most of the time when I get called for this, it's either Wrinkle Prevent running exactly as designed or sensor bars so coated in dryer sheet wax that the dryer genuinely can't tell the clothes are dry. Ignore it long enough and you're wasting a ton of electricity or, worse, risking a stuck motor relay that keeps the drum spinning even with the door wide open.
Samsung Dryer Won't Stop Running: Sensor and Relay Fixes
Most homeowners assume the timer's broken, but on modern Samsung dryers it's usually way simpler than that. You're either dealing with a setting that's working exactly as intended, a sensor that can't read moisture because it's coated in fabric softener residue, or a relay that's stuck on. Figuring out whether there's still heat running while it tumbles is your first clue to which one you've got.
Most Likely Causes
Based on aggregated repair data, here is the probability breakdown for this error code:
Moisture sensor failed30%
Timer contacts welded20%
Thermostat stuck15%
Board relay stuck15%
Wrinkle prevent (normal)10%
Cool-down extending10%
Symptoms You May Notice
The dryer keeps tumbling 45 minutes to an hour past when the clothes are completely dry and warm to the touch
Pressing Start/Pause doesn't stop the drum, or it stops for a second and then restarts on its own
Dryer shuts off, then kicks back on 10 or 15 minutes later with no heat (don't panic, this one's usually just Wrinkle Prevent)
Clothes coming out over-dried, stiff, and way hotter than they should be
Electric bill creeping up and the dryer running noticeably longer than it used to on the same size loads
Can you reset a Samsung dryer to clear the NOT-TURNING-OFF code?
Unplug the dryer or flip the breaker and leave it off for a full 10 minutes. That gives the capacitors on the control board time to fully discharge and clears any software glitch that's holding the motor command. While it's unpowered, wipe down both metal sensor bars inside the drum with a cloth and rubbing alcohol. Then plug back in and run a small test load to see if the cycle ends normally.
Tools Required for Diagnosis
Phillips #2 screwdriverFlat-head screwdriverMultimeter with continuity settingCotton balls or clean clothIsopropyl alcohol (90% or higher)Work glovesFlashlight or headlamp
Diagnostic Checklist
Follow these steps in order. We start with the easiest external fixes before opening up the machine.
Frequently Asked Questions
How much does fixing a Samsung dryer that won't stop usually cost?
If it's just dirty sensors or Wrinkle Prevent mode, the cost is literally zero. Cleaning the bars takes five minutes and a cotton ball with rubbing alcohol. If you need a new control board, that's where it gets real. The board itself usually runs $120-$180 for Samsung parts, plus a couple hours of labor if you're not doing it yourself, so total repair is typically $150-$350 depending on your area. Honestly, if the dryer's over eight years old and needs a board, start shopping. That repair cost gets close to what you'd spend on a decent new unit on sale.
Is it worth repairing or should I just replace it?
Under seven years old, I'd fix it. Samsung builds these solid enough that a single board or sensor replacement will usually get you several more good years. But if the motor's also making noise, or the drum rollers are squealing, or more than one thing is going wrong at once, those combined costs change the math fast. Also worth checking whether your model still has parts available. Some older Samsung dryer series are getting harder to source, which drives up prices even more and makes replacement look a lot more sensible.
Can I fix this myself?
Absolutely, for the easy stuff. Cleaning the sensors or disabling a setting is something any homeowner can do in five minutes, no tools needed. Replacing the control board is more involved but it's really just a screwdriver job and being careful with plastic clips, nothing crazy. If you've got a gas dryer and you suspect the problem goes beyond sensors or the board into the igniter or gas valve area, that's where I'd say call a pro. Not worth the risk messing with gas lines if you're not comfortable with it.
Why does my Samsung dryer start back up by itself after it stops?
Nine times out of ten, that's Wrinkle Prevent doing exactly what it's designed to do. It's supposed to restart the drum every few minutes after the cycle ends, no heat, just tumbling, to prevent creases. If Wrinkle Prevent is definitely off and it's still restarting on its own, then you've got a stuck relay on the control board. That's a different situation entirely and usually means the board needs to come out. A stuck relay means the motor never truly gets the signal to stop, regardless of what else you do.
Can dirty moisture sensors really cause the dryer to run forever?
Yes, and it's way more common than people think. I replaced three sets of sensor bars just last week on Samsung dryers where the homeowner had been using scented dryer sheets for years. Here's the thing: the sensor works by measuring electrical resistance between the two bars. When clothes touch both bars, current flows differently based on how wet the fabric is. When those bars are coated in wax, they can't get a clean reading, so the dryer just assumes the load is still wet and keeps going. Clean the bars, problem solved, usually in under five minutes.
Same Fix Works on These Brands
Samsung shares the same hardware platform with these brands. The diagnosis and repair steps are identical.