HP 15C All segments on

[Allen]

(05-26-2020 03:06 PM)howardlong Wrote:  As soon as the cells are inserted, and before pressing any buttons, the display came up with all segments on, including annunciators.

I seem to recall something like this happening to me once when the batteries were removed at completion of a self-test. It's possible the calculator is damaged? I read somewhere that in lieu of the "short" test, one could insert the cells backward for a moment.

I checked the user manual which only says reversing the cells "will clear Continuous Memory and could damage the batteries." So I assume the calculator is protected against reverse voltage. (maybe only try this with cells that are nearly dead anyway?)

If that does not enable key response ( I'd run the self check and keyboard check at the link Bob added), I'd say the calculator needs to be repaired.

Which brand and model batteries are you using? I like the LR44 or A76 batteries.

Not as common, but I've had problems with some of the cheaper Chinese batteries (apparently) not sourcing enough current on startup or during self-test, which generated lots of "Pr Error" messages each time the calculator went into brown-out.