If your calculator does not appear to light up, it could be that the contrast is at a low setting. Use this guide to aid you in adjusting the contrast.
Remove the front protective cover by sliding it off of the calculator.
Press the "ON" button to turn on the calculator.
Press the "2ND" button at the top left portion of the keypad. An arrow pointing up will appear at the top left corner of the screen.
Press and hold the "UP" arrow until you have increased the contrast to a level that is easily visible for yourself. A common level to set the contrast is 5.
To decrease the contrast, press the "2ND" button, then press and hold the "DOWN" arrow.