HP-41C Shows 12 Commas, Otherwise Unresponsive

[burkhard]

(04-23-2019 03:09 PM)Diego Diaz Wrote:  Hi, Since it's a 41C chances are that it's a "coconut" model (AKA fullnut) therefore the CPU board is connected to the keyboard/display assembly by some elastic connector.

The plastic posts holding the screws are well known to cause these kind of symptoms (and many others) when the plastic cracks and the connection between both boards gets loose.

I was thinking the same thing. If you squeeze the top and bottom of the calculator together with your fingers (try a few places) while attempting to power/de-power, does it help?