I have two broken TI-83 Plus Silver Editions. I hope it's OK that I am putting both in this one topic, but I can create a second one if I need to.

Here's the story:

I have a TI-83 Plus Silver Edition that I've been using for about 12 years. I was just using it this spring for a math class. I'm now taking a couple more in the summer, but when I went to use the calculator on the first day of class, it would not come on. I assumed the batteries were dead and replaced them with new ones, but that didn't help. Finally I realized that the batteries were not dead to begin with (tested them in another calculator), but the screen's contrast was just super low. Upon turning it up, I found that the screen was just a solid black block. I could connect to it with TI Connect, and it was running normally, the display was just useless. I took it apart and jiggled the ribbon cable connecting the display to the motherboard, and that got the screen to show something. Unfortunately, it only displays the left fourth of the screen or so. With this information, and a lot of Googling, I've determined that the ribbon cable is probably screwed up, as that seems to be quite common. I've removed it and am going to attempt to solder replacement wires tonight. Hopefully, that will fix the first calculator.

I mentioned these problems to my dad, who told me that when I first got my TI-83 Plus SE, it stopped working just a few months in, and we got a replacement (the one above with the screwed up display). I had actually forgotten all about this, but he still had the older calculator. I put new batteries in it, and here's what I've found about it:
You can get it to turn on sometimes. Sometimes just pressing On works. Sometimes you have to remove a battery and replace while holding Delete. Neither method always turns it on. Once it is on, it turns back off pretty quickly (but seemingly at random). Every time it turns on, it says that RAM was cleared. I found some people online with this problem, but have been unable to find any solution. Is this just not fixable by a user? If it isn't, can you still return these things? I know they are ancient!

Unfortunately, they are definitely out of their warranty period now, and to my knowledge TI doesn't still manufacturer the calculators anyway to send you replacements (although I might be mistaken). For the first calculator, what you're describing is classic ribbon cable failure. You probably already found my guide to repairing TI-83 Plus LCDs, which is what you should follow for fixing that calculator. The other one is a bit trickier, and although I have calculators with those symptoms in my extensive collection, I haven't yet found a solution. It's possible that it might be a loose battery contact, though.

I assumed they would be out of warranty, haha! Bummer. I have indeed seen your guide, and its existence is why I posted on this forum! I have never soldered anything before, so tonight I ended up just soldering random stuff around my house for practice.

For the second calculator: I tried cleaning the battery contacts, as well as moving them about, but to no avail. I kind of figured its problem might be less solvable... It seems like it is losing power constantly, and then every once in a while it gets it back briefly. Weird.

I'M not sure why but I always had the impression that the TI-83 PLus Silver Edition calculators had a much higher failure rate than the TI-82/83/83+/84+/84+SE, because in the past, LCD problems (although usually garbage appearing) were very common on such calcs on calc forums and in my case, the two calcs I got in the past had loose screws in the middle. Maybe the assembling quality wasn't as great as with other models?

The only other models that seems to have an higher failure rate are the TI-80 and the TI-Nspires with removable keypads.

OK, probably going to just give up on the second calculator. The first one, with the display problems, lives again! Took a bit longer than I planned, but I have never soldered anything before. It turns out that my wife is way better than me at all these tiny things, and she sat down and soldered the whole thing in minutes. So far the display is working perfectly again.

At the worst case, try soldering two wires directly to the pads on the mainboard that the battery case contacts touch, and feed 6V to them to see what happens. Very nice job! I salute her soldering skills, as that is neatly done.

Oh, good idea! That would be easy to try, I believe I will do that. I'll report my results.


Thanks, that was her first time soldering, too!