Verifying Proper Operation (Self Tests) - HP -11C Owner's Handbook Manual

234 Appendix D: Battery, Warranty, and Service
Verifying Proper Operation (Self-Tests)
If it appears that the calculator will not turn on or otherwise is not
operating properly, use the following procedures.
For a calculator that does not respond to keystrokes:
1. Press the and keys simultaneously and 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 that the batteries are
properly positioned in the battery compartment: the flat
sides (the sides marked +) should all be facing toward the
nearby rubber foot.
3. If the calculator still does not respond to keystrokes, leave
the batteries in the compartment and short the battery
terminals together. (The batteries must remain in place to
prevent possible internal damage to the calculator.) With a
paper clip or a piece of wire, briefly connect the terminals.
Only momentary contact is required. The terminals are
matching metal strips, or a combination of one spring and
one hard edged tab located at either end of the battery
compartment. After you do this, the contents of 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 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 [x].
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 25 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