Cordless SEBO vacuum runs but shuts off when brush mode is engaged; red fault indicator flashes three times repeatedly.

Safety first: Remove the battery pack before working on the brush head. Never place fingers near the brush while power is connected.

• Remove the brush head: Detach the power head from the wand or main body. Open the brush access panel (usually via clips or screws on the underside).
• Clear the brush roller: Remove hair, threads, and debris wrapped around the brush roller and end caps. Use scissors carefully to cut away tightly wound material.
• Check brush bearings: Pull the brush roller out (if removable). Spin the end caps with your fingers. They should rotate smoothly. If they feel gritty, stiff, or seized, replace the brush roller assembly.
• Inspect belt/drive: If your SEBO cordless head uses a belt or gear drive, check for broken, stretched, or melted belt, or damaged gears. Replace the belt or brush drive module if worn.
• Check brush motor: With the brush roller removed and battery reinstalled, briefly power on and switch to brush mode while holding the head clear of surfaces. If the brush motor does not spin or makes loud grinding noises, the brush motor is likely faulty.
• Reassemble and test: Refit the brush roller, close the access panel, and test again. If E3 persists, the brush motor or brush motor driver circuit on the PCB may need replacement.