A blown or disconnected fuse can cause the LCD screen to appear blank
If the 2.5A fuse shown here on the latest (2022) generation SuperSting is not connecting correctly or is blown, the LCD will be blank and the power switch will not function. In some light, the screen may also appear blank if the contrast is turned down. You can fix that here.
This fuse only connects by design when two metal tabs are properly aligned and you do not press on the fuse holder which removes the tabs from connection. Details on the 2.5A fuse are HERE and more details on the various fuses is HERE.
T0 OPEN the fuse: press down with light pressure and rotate the fuse a quarter turn to the left counter clockwise. Lift out the fuse holder and remove the fuse to place it on a non conductive surface like an anti static mat or wooden table. Check the fuse with an ohm meter or continuity check. Visual checks do not work because the fuse can be blown behind the metal cap.
To CLOSE the fuse: carefully align the two tabs shown above with the groove in the fuse holder and insert the fuse while pressing down and turning a quarter turn to the right clockwise.
Details on the fuse specifications are found HERE
Leaving the fuse holder open during transport and typical field conditions allows contaminates to enter.
Losing the fuse holder caps eliminates system functions.
Pressing firmly on the fuse holder removes electrical connection by design which can interrupt a survey if you do this while measuring.