Help I got a TI-83 plus calculator and when i turn it on the whole screen is black.I try to use the up and down contrast to make it darker or lighter but it doesnt do anything. Anyone no

Either you need to change the batteries or you need to adjust your contrast. To adjust the contrast, press [2nd] [down arrow] or [up arrow] to adjust it lighter or darker. From your description, it sounds like you need to press the down arrow to make it lighter. Hope this solution helps. Reply back if it doesn't.

All you need to do is press [2nd] and the down arrow to lighten up your contrast. The problem is that your contrast was to dark. Hope this solution helps!

First make sure that the batteries are fresh and that they are inserted with their poles in the proper position. Secondly hit the "2nd" key and hold down up. This is the contrast adjuster which makes the screen images lighter or darker. I have seen many students complain about a broken calculator when it is just not adjusted properly.
Good Luck

This really sounds like a problem with the contrast. Try this: turn the calculator on; press the second key, and then press and hold down. This she reduce the dark contrast.
Good Luck

To alter the contrast (light/dark) of your screen, press "2nd", then press your up and down arrows to make the screen darker or lighter, respectively.

The "color" on your screen reset to dark. You can adjust it by pressing "2nd" and the "up" arrow (or "2nd" and "down" arrow) repeatedly.

This is from TI FAQS:

Solution 11900: Troubleshooting a TI Graphing Calculator That Will Not Turn On.

For the TI-83 Plus Family, TI-84 Plus Family:
Caution: The resets described in these troubleshooting steps will cause a loss of applications, programs and data. If at all possible please create a backup using TI Connect™ first.

1. Try a new set of AAA batteries.
2. Adjust the contrast by pressing and releasing the [2nd] key followed by pressing and releasing the up arrow; repeat as necessary. To adjust or lighten the display, use the down arrow.
3. Remove one of the AAA batteries. Press and hold the [CLEAR] key. While holding [CLEAR], reinsert the AAA battery and then turn the calculator on. The calculator should display the message "RAM Cleared". Release the [CLEAR] key and then press it one more time to remove the message.
4. Remove one of the AAA batteries. Press and hold the [DEL] key. While holding [DEL], reinsert the AAA battery and then turn the calculator on. The calculator should display "Waiting...Please install calculator software now". Follow the instructions for the TI-83 family or TI-84 Plus family to reinstall the calculator operating system.
5. Remove all of the batteries including the round lithium battery for 5 minutes. After the 5 minute period, reinsert all of the batteries and turn the calculator on. Adjust the contrast if necessary.

try pressing 2nd then hold in down arrow to change the contrast

Try pressing the 2nd key and then holding down the up arrow key first.  This changes the contrast on the screen- makes it darker.  Pressing the 2nd key and then holding down the down arrow key will make the screen lighter

you have to press the 2nd key, then the up or down arrow. up for darker screen, and down for a lighter screen.