Sharp EL9900C EL-9900C - Page 241

Appendix 2. Troubleshooting Guide Refer to the list of possible symptoms, and solutions may be found here. The calculator's power won't turn on! • The operation batteries may not be installed, may be exhausted, or may be inserted incorrectly. Check the operation batteries in the battery compartment. • Place the battery cover securely or the calculator will not turn on. The saved calculator configurations are not retained! • Both the lithium battery and the operation batteries may need to be replaced. The power seems to be on, but the characters and numbers cannot be seen clearly on the display! • The screen contrast may need to be adjusted. Press @ p, then press A to enter A CTRST; the screen contrast can be adjusted by using the + or the - key. The calculator won't take the minus (-) sign; calculation results in a syntax error! • To set a negative value, use the _ key instead of the key. The calculation results are very different from what is usually expected! • The angle unit and other configurations may be incorrectly set. Check the configuration under the @ ;. The graph cannot be seen! • Check the zoom configuration. Try selecting the automatic zoom tool, by pressing Z, then A 1. • The graph line may be set differently; check the line configuration under @ d menu. • The calculator may not be set to display graphs. Check the "=" sign in Y= screen. 231