Error 30 indicates an communication issue between the display of your bike and the internal controller. Somehow, the two aren't communicating properly and the majority of the time, this is a loose connection, bad settings, or a damaged cable.
First, try resetting your display to default. This is done from the main screen by holding the middle (Power) and top (+) button on your display at the same time. Select reset to default 'yes' and hold the middle button to enter that setting. These steps can be shown on our display tutorials.
Next, follow this guide on checking connections (Section B and C). If you are methodical in your inspection, you will likely resolve this issue faster.
After you have checked your connections and reset your display. It is an appropriate time to contact our support team.
This error may require a replacement internal controller, or a replacement display. If you have access to another bike and you are able to test a replacement display, this may help in expediting the troubleshooting process.