41C and 41CV won't power up...


Both worked when last used, about a month or two back. Been stored w/o batteries. There's no battery corrosion. Batteries are good. Any suggestions?

Many thanks.


I suggest the following:

After removing the batteries, wrap the fingers of one hand loosely around the lower end (bottom of keyboard); wrap fingers of other hand loosely around the upper end (across the display). VERY gently twist the calculator about its "longitudinal" axis (remember, VERY gently is the key) back and forth a few times. You will probably hear and "feel" it creaking a bit.

Reinstall batteries and see if it powers up. Sometimes the gentle twisting will "reconnect" some of the press fit connections between the front and back halves of the calculator.

If this doesn't work, the next thing I would try is separating the case halves and cleaning every visible contact with alchohol (rubbing alchohol, not vodka). Be very careful removing and reinstalling the four screws (which are under the rubber feet) because the screw posts will break fairly easily and they are a royal b*#@$ to fix. In fact, you may want to check for loose screws before you separate the case halves. The pressure of the tightened screws is essential to the two halves making good contact, but there is a fine line between poor connections and over-tightened, broken-posted screws. You want to be right there in between the two situations.

Good luck. That is the extent of my knowledge of "repairing" 41C series calculators which will not power up.

Take care.


PS - It is curious that they BOTH worked a few months ago and that they BOTH don't work now. Were they stored together? Could they have both been exposed to stray static charges or Electromagnetic frequencies? Was there any atmospheric nuclear testing in your neighborhood recently?


Perhaps one of the techniques presented here would be helpful.


Maybe corrosion of the springs in the battery holder? I face this problem from time to time. The springs do not give much pressure on the batteries and from time to time I have to clean them and do some readjusting.
Hope it helps....



Take apart the machines and clean all the pressure contact areas with 91%+ isopropyl alcohol. Don't forget the contacts under the CPU board in fullnut machines.

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