You probably did this but just in case...
There are three types of reset available for the display:
• Factory Reset: This resets all values back to their original factory settings.CAUTION:The factory reset clears the Marks database and, on the SL72RC PLUSchartplotter, the Waypoints and Routes databases.
• Power-On Reset: When you turn the display off and on again, the screen reverts to the fishfinder or chart picture with all windows cleared.
• Picture Reset: Press and hold the DISPLAY key for two seconds to return the screen to the full-screen picture of the top window with all windowscleared.At power-on, the last-used values are retained for all the options, except for those listed in the following table which are reset to the factory default each time.Table 9-1:ItemHeading ModeRainFTCAlarmZoomWindowsContrast LevelBacklight Level➤ To perform a factory reset:1. Press MENU .2. Press the SYSTEM SET UP soft key to display the System Set Up page (see Section 7.3 for details).3. Press and hold MENU for 5 seconds.A countdown timer is displayed. If you release the MENU key before the timer reaches zero, the reset is not performed.When the reset request has been accepted, the system restarts