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+--- Thread: 12C display not working (/thread-19659.html)
12C display not working - Brianr88117 - 03-14-2023 05:05 PM
Hello,
I am new to the forum and a complete beginner. I own a 12C which I purchased back in 2014. I used it for about a year then it went into my top drawer in its leather case, not to be used until recently. When I turned it on, the display hardly showed any numbers, but it was attempting to show me some. I changed the batteries to ones from a pack that I had in a drawer, but that yielded the same results.
Upon a serial number check this calculator was made in China in 2012, which doesn't seem that old compared to what I'm reading about the history of this calculator.
I tired the reset button located near the battery compartment, no change. I tried the (-) sign reset no change. I tried the paper clip to connect the + and -, and drain the capacitor, no channge. Before I purchase another 12C, I was hoping there was a way to fix this.
I did read that someone warmed up the screen connections from the inside, but I have no idea on how to open this up properly.
Any help would be appreciated.
RE: 12C display not working - rprosperi - 03-14-2023 09:35 PM
Before you do anything else, I suggest you try it with new, good-quality CR2032 batteries; from your description, it sounds like the batteries may have been sitting around a while. When batteries are low, behavior of these machines is odd and nor easily predicted or consistent.
Remove both old batteries, short the terminals in the bay, press [ON] to bleed any residual charge in the board and let it sit empty until you get the new 2032 cells (but at least overnight).
Let us know how it goes.
RE: 12C display not working - Maximilian Hohmann - 03-14-2023 09:49 PM
Hello!
And a (perhaps) stupid question from me: Did you try to increase the display contrast? The newer 12Cs, to my knowledge all models that are powered by CR2032 cells, have that function: press "f" together with "+" or "-" to change the contrast.
Regards
Max
RE: 12C display not working - Mark H. Shin - 03-15-2023 01:40 AM
Welcome to the forum!
I'm afraid this condition seems to be a common affliction of the earlier releases of the new 12C with 2 CR2032 (S/N beginning with CNA; 4CY; and others).
It appears to be (in my humble opinion) a systemic flaw...
P.S. You can implement your mentioned heating method, without opening the unit, by simply placing the unit in the sunlight for some time, but it remains a very temporary fix at best...