Texas Instruments TI-83 Manual page 22

SEC but also all the keystrokes needed.
Troubleshooting
The screen is fading.
Solution. With the calculator on, press the key 2nd
and release. Now press the key and hold it. You
should see the screen brighten and a number appear in
the upper right-hand corner. This number tells you the
status of your battery. When the number approaches
10, your battery is about dead.
Strange graphs appear when I graph.
Solution. When you press the Y = key you see a list
of eight functions. Scroll down the screen and you will
discover two more functions. If some of those functions
have formulas, that is your problem.
Another possibility is that under STAT PLOT some
of the graphs have not been set to off.
My link failed.
Solution. You probably didn't press the connecting
wire hard enough. Press the wire very hard into the
calculator.
I transferred a working program to my calcula-
tor and my program is not working correctly.
Solution. Unfortunately, my experience has shown
that about 5% of links fail by not transferring the entire
program. Transfer again, using overwrite. This should
work.
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