My calculator is very dim and i can barely see the numbers. I changed the batteries and it is still happening

LCD screen is separating. It happens over time to all LCDs. It is shot. Should be able to lightly press on it while you are calculating and see the numbers fine.

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

The button cell backup battery keeps the memory electrically refreshed when the calculator is turned OFF. The necessary power for regular use is supplied by the 4 AAA batteries (main power). That nothing happened when you put in a fresh set of (expensive) lithium batteries may be due to the screen being too dim to see anything.

If the calculator displays RAM CLEARED each time it is turned on, it may be due to a depleted backup battery. The battery model number is CR1616 or CR1620. On my TI84PLUS the backup battery is of type 303 (Sony) or SR44SW (Maxell).

Have you tried new batteries?

It is possible that it is turned ON but you cannot see what is on the display because the screen is too dim. That often happens after you change batteries.
To make the screen darker

1. Press the [2nd] key and release it.
2. Press the [UpArrow] key and HOLD it pressed until the screen darkens to your liking.

Not if the backup battery's good---that's what it's there for. You may not be able to read the screen afterward, 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. If this happens, 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.

Hello,
After the change of batteries, the screen reverted to default contrast. You should try to darken the screen.
Press and hold the [Diamond] key and tap the [+] key. Keep at it until screen is dark enough.
Hope it helps.

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 at all. 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.

Have you attempted darkening the display on the calculator through the function keys? Push "2nd" and then push "up" a few times. After resetting the calculator, this setting will always revert to a lower, unreadable setting. I'm sure TI knows about this, but they probably arent too inclined to fix it.