I just changed the batteries in my TI-84 plus and when i turn it on it says that the batteries are low and should be replaced, but i just bought them two hours ago

TI calculators have an annoying habit of dimming the screen, especially when the batteries are changed, so that it appears as if the calculator isn't turning on. Turn the calculator on (or at least press the ON key). Press and release the 2ND key. Press and hold the Up-arrow key for a few seconds and see whether the screen becomes legible.
If this doesn't do it, please reply to this post and we'll go on to the next step.

Double check batteries and polarity first. If this doesn't help, return it to the store, you have a DOA (dead-on-arrival) machine. They're obligated to replace.

TI calculators have an annoying habit of dimming the screen when the batteries are changed so that it appears as if the calculator isn't turning on. Turn the calculator on (or at least press the ON key). Press and release the 2ND key. Press and hold the Up-arrow key for a few seconds and see whether the screen becomes legible.

If that doesn't work, remove all four AAA batteries. Press and hold the ON key for ten seconds. Replace the batteries.

If that doesn't fix it, please append a comment to this post and we'll go on from there.

TI calculators have an annoying habit of dimming the screen when the batteries are changed so that it appears as if the calculator isn't turning on. Turn the calculator on (or at least press the ON key). Press and release the 2ND key. Press and hold the Up-arrow key for a few seconds and see whether the screen becomes legible.

If that doesn't work, add a comment to this post and we'll go from there.

Remove all four AAA batteries. Press and hold down the ON key for at least ten seconds. Replace the batteries. Turn the calculator on.

The problem may be due a screen that is too light to see anything on it. Adjust the screen darkness.

1. Press [2nd] key and release it.
2. Press and HOLD the [UpArrow] to draken screen.
3. Release the [UpArrow] when screen is dark enough.

You can also connect it to the computer to see if TI Connect finds it. If it does, update the OS to version 2.53MP.

You change the backup battery if the calculator tells you RAM CLEARED each time you turn it ON.

Yes we changed out the batteries on now the TI-84 will not turn on HELP

Your sure every battery was put in correctly and was good? When I first got mine I thought I had the batteries in correctly but, I didn't.

ON, 2nd, [up] arrow to change the contrast. Works 99% of the time....

thats cuz the OS is corrupt