A flashing screen will indicate an issue with the safety key. So before starting your treadmill up please ensure the safety key is in place on the monitor. The safety key works on a magnet connection.
If you have ensured the safety key is in place and your monitor is still flashing then it could be the magnet on the underneath of the monitor that needs slight adjustment so a connection can be made. Check underneath the tray to see if the wire connection is aligned with the magnet and tighten the screw.
There is also a wire connection that connects to the magnet, if the wire has been pulled to hard the connection may have been lost or the wire has damage then this again can affect the performance of the machine.
If you have been unable to resolve your issue then please contact us for more information.