The dF error means door switch not detecting door as closed — dryer won't start.
The Samsung dryer displays the dF error and halts the current cycle until the underlying problem is fixed.
Check these in order. The first cause accounts for the majority of dF errors.
The most common cause by far — the door needs a firm push to fully engage the latch. Try pressing the door closed firmly from the center of the door and retry start.
The plastic latch hook can crack or round off with repeated use, preventing full engagement. Inspect the latch with a flashlight.
The door switch behind the door frame sends the 'closed' signal to the control board. If the switch contacts fail, the board never receives the signal even when the latch is engaged.
The wire harness running from the door switch can break near the door hinge after years of repeated opening and closing.
Follow these in order. Stop as soon as the error clears.
Push the door closed from the center with both hands. Listen for a solid click from the latch.
If re-closing doesn't help, disconnect power before inspecting components.
Open the door and examine the plastic latch hooks. Visible cracks or worn-down hooks require latch replacement.
With the machine unplugged, manually push the latch mechanism and listen for a crisp click from the switch behind the door frame.
Disconnect the switch wiring and test with a multimeter. Should show continuity when the latch is manually depressed. OL reading = failed switch.
If the latch or switch is faulty, replace the assembly. Most Samsung dryer door latches clip in and require no special tools.
For warranty service, contact Samsung support ↗ or a certified appliance technician.