Dryer stops with E13; on some models, the drum may stop suddenly as if jammed.

Safety first: Unplug the dryer. Moving parts can cause injury; ensure the drum cannot start unexpectedly.

Step-by-step checks:

• Check for mechanical jam: Open the door and rotate the drum by hand. If it binds or grinds, inspect for foreign objects between drum and cabinet before suspecting electronics.
• Access the motor: Remove the rear or side panel to expose the drive motor. Locate the tachometer sensor at the rear of the motor (often a small plastic module with two wires).
• Inspect tacho magnet: Ensure the magnet ring or disc on the motor shaft is intact and not cracked or loose.
• Test tacho coil: Disconnect the tacho wires and measure resistance with a multimeter. Typical values are a few hundred ohms. An open circuit indicates a failed sensor.
• Check wiring: Follow the tacho wires back to the control board, checking for damage or loose connectors.

When to call a technician: If the tacho and wiring are good, the main control board's speed sensing circuit may be defective.