Casio fx-991W Calculator User Manual


 
E-31
Technical Information
k When you have a problem......
If calculation results are not what you expect or if an error
occurs, perform the following steps.
1.
F 1 (COMP mode)
2.
F F F 1 (DEG mode)
3.
F F F F 3 1 (NORM 1 mode)
4. Check the formula you are working with to confirm it is
correct.
5. Enter the correct modes to perform the calculation and
try again.
<
fx-570W/
fx-100W
>
If the above steps do not correct your problem, press the
P button (see page 35 or 36) on the back of the calculator
to reset it. Pressing the P button deletes all data stored
in calculator memory. Make sure you always keep written
copies of all important data.
<
fx-991W/
fx-115W
>
If the above steps do not correct the problem, press the
5 key. The calculator performs a self-check operation and
deletes all data stored in memory if any abnormality is
detected. Make sure you always keep written copies of all
important data.
k Error Messages
The calculator is locked up while an error message is on
the display. Press
t to clear the error, or press e or r
to display the calculation and correct the problem. See
“Error Locator” on page 10 for details.
Ma ERROR
•Cause
•Calculation result is outside the allowable calculation
range.
•Attempt to perform a function calculation using a value
that exceeds the allowable input range.