I bought a ti 84+ se calculator for $4.99 from Goodwill. It has a socket like it can be hooked up to a projector. The calculator doesn’t work. I tried new batteries, increasing the screen brightness, holding down the clear key while inserting the batteries, etc. I can’t think of anything else to try. Nothing shows on the screen so I don’t know if the screen is bad, or something else. I can take it back, but I’m thinking of just taking it apart to see if I can see anything wrong or just to see what’s inside. The problem, the screws. They look like torx screws. I have some torx bits, but they’re way too big. Does anyone know what size torx screws are in the ti 84. T1 is the smallest torx size, but I don’t know if that’s what they are. The calculator looks like it’s in great shape so I expected it to work when I bought it. I have 2 other working TI 84 plus SE calculators, so it doesn’t matter if I end up just destroying this, but I’d like to try whatever I can before that point.

I also bought a TI 83 Plus for $4.99 at the same time and that one works perfectly.

The screws are Torx T-6. Be careful when you take the calculator apart not to accidentally rip the cable that connects the motherboard to the projector socket. Just take a spudger to pop all the snaps that hold the calculator together, then slowly pull the two parts of the shell apart.

Could you please tell us the date code on the back of the calculator? It looks something like L-0519M.

Did you also replace the coin cell backup battery?

TheLastMillennial; Thanks for the reply on the T-6. The code on the back is P-0511N.

TheLastMillennial; I just tried new batteries along with a new coin cell battery. Nothing. The screen is just blank.

Does whichever computer <-> calculator transfer software you're using detect your calculator, and is this software able to grab screenshots ?

Lionel Debroux I have nothing to hook a calculator to a computer. I mostly just collect calculators so a lot of time it doesn’t really matter if they work or not. Since I already have 2 working TI 84 Plus SE calculators, it isn’t that important if it works or not. I was just hoping that I could get it working. I’m headed to the store now to get a T-6 bit so I can open the calculator. If I end up destroying it, at least I’ll see the inside of it.

Alright. At least, the 84+SE has a mini-USB port, unlike a number of older models, so it doesn't require a custom cable - only custom software.

I got the T-6 bit. Took the 6 screws out and had a hard time getting the case seperated until I realized that the screw that was holding the coin battery cover was also holding the case together. Got it opened, looked around but didn’t see anything wrong. Not that I would’ve recognized anything anyways. I folded the foil that was covering the display back and took my finger and ran it back and forth along the ribbon cable thinking it might be loose from the display. There was nothing else I could see worth trying. I wasn’t going to take it apart any more than it was because I don’t know what I was doing anyways. I put it back together, put the batteries back in and pressed on. The screen went black then said RAM Cleared. I pressed on again and it seems to be working OK. The sides of the case are really roughed up from trying to pry it open, but I’ll smooth that out later. It still works, so I guess it was just a loose cable connection on the display. I’ll play with it for a few days just to make sure it still works then remove the batteries and put it in the box with my other calculators.