HP 12C Platinum Owner's Handbook Manual page 193

Appendix F: Battery, Warranty, and Service Information
For a calculator that does not respond to keystrokes:
1. Insert a thin, pointed object all the way into the reset hole near the battery
compartment and then remove it.
1. The display will show Pr Error. Pressing any key will clear this message
from the display.
2. If the calculator still does not respond to keystrokes, remove and re-insert
the battery. Make sure that the battery is properly positioned in the battery
compartment.
3. If the calculator does not turn on, install a fresh battery. If there is still no
response, the calculator requires service.
For a calculator that does respond to keystrokes:
1. With the calculator off, hold down the ; key and press §.
2. Release the ; key, then release the § key. This initiates a complete test
of the calculator's electronic circuitry. If everything is working correctly,
within about 15 seconds (during which the word running flashes) the
display should show –8,8,8,8,8,8,8,8,8,8, and all of the status indicators
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If the display shows Error 9, goes blank, or otherwise
should turn on.
does not show the proper result, the calculator requires service.
1.
The status indicators turned on at the end of this test include some that normally are not
HP
displayed on the 12C Platinum.
2.
If the calculator displays Error 9 as a result of the ;/§ test or the ;/+ test but you
wish to continue using your calculator, you should reset Continuous Memory as described on
page 70.
ersenkte Reset-Taste
197
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