HP 35s Self Test
Turn on the HP35s, and press and hold [C], and the press [XEQ].
Press any key 8 times to test the LCD Panel. You see KDB 01. Press the key from left to right and top to down. See the key test map below.
If you follow the sequence, you end up ‘35S-OK’. If you get ‘35S-FAIL 8’ the error mid-way, you could have press the sequence wrongly. Press [C] [GTO] together, to terminate test, and repeat the test again.
To run continuous system test, press [C] [MODE] at the same time. Press any key to terminate the test.