Verifying Proper Operation (Self-Tests) - HP -10C Owner's Handbook Manual

100 Appendix C: Battery, Warranty and Service Information

Verifying Proper Operation (Self-Tests)

If it appears that the calculator will not turn on or otherwise is not operating
properly, review the following steps.
For a calculator that does not respond to keystrokes:
1. Press the Y and = keys simultaneously, then release them. This
will alter the contents of the X-register, so clear the X-register
afterward.
2. If the calculator still does not respond to keystrokes, remove and
reinsert the batteries. Make sure the batteries are properly positioned in
the compartment.
3. If the calculator still does not respond to keystrokes, leave the batteries
in the compartment and short both battery terminals together. (Fold
back the plastic flaps to expose the terminals, which are the metal strips
on either side of the battery compartment.) Only momentary contact is
required. After you do this, the contents of the Continuous Memory
will be lost, and you may need to press the = key more than once to
turn the calculator back on.
4. If the calculator still does not turn on, install fresh batteries. 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 (except the * low-power indicator) should turn
on.* If the display shows Error 9, goes blank, or otherwise does not
show the proper result, the calculator requires service.†
Note: Tests of the calculator's electronics are also performed if
the + key or the ÷ key is held down when = is released.†
These tests are included in the calculator to be used in verifying
that it is operating properly during manufacture and service.
*
The status indicators turned on at the end of this test include some that normally are
not displayed on the HP-10C.
†
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 18.
‡
The = / + combination initiates a test that is similar to that described above, but
continues indefinitely. The test can be terminated by pressing any key, which will halt
‡