A red light on your Oral-B electric toothbrush could be one of the following four things:
• Oral-B Visible Pressure sensor: Many of our toothbrushes feature a visible pressure sensor. If you're pressing too hard on your teeth, it will light up. Remember there's no need to brush hard or scrub -- move the toothbrush slowly from tooth to tooth and let the brush do the work.
• Stuck toothpaste: Is the pressure sensor lit up all the time? Sometimes a bit of toothpaste can get stuck around the metal pin which connects to the brush head, and this can trip the pressure sensor. To fix this, try rinsing the metal pin and handle under warm water for at least ten seconds. To prevent this in the future, make sure after every use to remove the replaceable brush head and rinse both parts, before drying and storing them separately.
• Low battery indicator: If the red light is near the bottom of the handle, this could be the low battery indicator (PRO 1000 and above). It lights up when it’s time to charge your toothbrush, as there is only enough power left in the battery for 1 or 2 more brushes. Now would be a good time to charge it.
• SmartRing: Lastly, the Genius toothbrushes feature a customizable SmartRing which provides visual feedback on your brushing pressure, brushing time and selected mode. Using the Oral-B App, you can change the color of this ring, and there are a number of colors to choose from.