262Appendix F: Battery, Warranty, and Service Information

Note: Tests of the calculator’s electronics are also performed if the = key or the zkey is held down when ;is released.* These tests are included in the calculator to be used in verifying that it. is operating properly during manufacturing and service.

If you had suspected that the calculator was not working properly but the proper display was obtained in step 2, it is likely that you made an error in operating the calculator. We suggest you reread the section in this handbook applicable to your calculation — including, if appropriate, Appendix A. If you still experience difficulty, write or telephone Hewlett-Packard at an address or phone number listed under Service (Page 264).

*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 the test within 25 seconds. The ;/zcombination initiates a test of the keyboard and the display. When the ; key is released, certain segments in the display will be lit. To run the test, the keys are pressed in order from left to right along each row, from the top row to the bottom row. As each key is pressed, different segments in the display are lit. If the calculator is operating properly and all the keys are pressed in the proper order, the calculator will display 12 after the last key is pressed. (The \key should be pressed both with the third-row keys and with the fourth-row keys.) If the calculator is not working properly, or if a key is pressed out of order, the calculator will display Error 9. Note that if this error display results from an incorrect key being pressed, this does not indicate that your calculator requires service. This test can be terminated by pressing any key out of order (which will, of course, result in the Error 9 display). Both the Error 9 display and the 12 display can be cleared by pressing any key.

File name: hp 12c pt_user's guide_English_HDPMF123E27

Page: 262 of 275

Printed Date: 2005/8/1

Dimension: 14.8 cm x 21 cm