The buttons of my casio cfx-9850GC plus ( buttons f1,f2,f3,f4,f5,f6) dont work. What can I do to solve my problem???

Their use depends on the application you are using. You press a function key to activate the TAB that is above it (at the bottom of the screen.)

You must have one of the newer OS versions (MP 2.53 and higher). You don't have anything under F5.

The function keys originally have twp functions: One function accessed by pressing a function key directly, the other by first pressing the 2nd key then the function key.
With the newer operating systems, there is a third function associated with the function keys F1.F2,F3 and F4, but not F5 nor F6. This third function is revealed after you press the ALPHA key.

Put the calculator in Equation solving mode. Select F3:Solver. Enter your equation; use X as unknow (no need to use Theta, the name of the variable is irrelevant.) Besides if you use theta you will get a syntax error.

In Run screen, enter the number whose factorial you want to calculate ( number can be at most equal to 69), press [OPTN][F6] to get to next page of menus.

For factorials

• Press then [F3](PROB) then [F1] (x!) followed by [EXE].

For combinations

• Press then [F3](PROB) then[F3][nCr][EXE]

For permutations

• Press then [F3](PROB) then[F2][nPr][EXE]

There is no button but a menu tab.
In Run screen, enter the number whose factorial you want to calculate ( number can be at most equal to 69), press [OPTN][F6] to get to next page of menus.

For factorials

• Press then [F3](PROB) then [F1] (x!) followed by [EXE].

For combinations

• Press then [F3](PROB) then[F3][nCr][EXE]

For permutations

• Press then [F3](PROB) then[F2][nPr][EXE]

GE / Hotpoint / RCA
Oven Fault Codes
Display Condition Remedy
F0 & F1 Failed Thermistor Control Replace ERC
F2 Oven Temp Exceeds 590 with unlocked door High resistance in Sensor, likely a bad sensor
F3 Open Sensor circuit Open (blown) sensor fuse or bad Sensor
F4 Shorted wire or Sensor locate short and correct it
F7-A Function pad button stuck Clean and unstick
F7-B Bad Clock Replace Clock
F8 Electrical component failure Replace ERC
F9 Program with door circuit Check wiring

Frigidaire / Westinghouse / Tappan / Gibson
Oven Fault Codes
Display Condition Remedy
F0 & F1 EOC failure Replace EOC
F2 Oven over heat Defective Sensor or EOC
F3 Oven Sensor Open Replace Sensor
F4 Shorted wire or Sensor locate short and correct it
F5 EOC failure Replace EOC
F6 EOC failure Replace EOC
F7 EOC failure Replace EOC


Maytag / MAYCOR / Magic Chef / Jennair / Admiral
Oven Fault Codes
Display Condition Remedy
F0 Function key shorted or stuck button Clean and unstick button or replace Touch Pad or Clock
F1 Defective Touch Pad or Membrane Replace Touch Pad or Membrane
F2 Oven over heat defective Relay Board or (if present) or defective Sensor
F3 Oven Sensor Open Replace Sensor
F4 Shorted wire or Sensor locate short and correct it or replace Sensor
F5 Hardware, safety circuits disagree Replace Clock
F6 Missing AC (power) signal Check for proper voltage (plug, breaker, etc.)
F7 Function key shorted or stuck button Clean and unstick button or replace Touch Pad or Clock
F8 A/D Warning Replace Clock
F9 Door Lock Warning Check door lock circuit or Replace Clock


Amana / Caloric
Oven Fault Codes
Type with display - glass link ERC
Display Condition Remedy
F0 No Safety Signal Replace adapter board
F1 No Safety Signal Replace ERC
F2 Oven over heat Replace defective Sensor
F3 Oven Sensor Open Replace Sensor
F4 Shorted wire or Sensor locate short and correct it or replace Sensor
F7 Shorted Touch Panel Replace Glass Panel
F9 Door Latch Error Check latch
FF Lock Error Check switch and motor
ERC III - Relay board with separate board/push buttons
F0 Shorted Push Pad Replace Push Pad
F1 Defective ERC Replace ERC
F2 Oven over heat Replace defective Sensor
F3 Oven Sensor Open Check/Replace Sensor
F4 Shorted wire or Sensor locate short and correct it or replace Sensor
F5 Defective ERC Replace ERC
F6 Defective ERC Replace ERC
F7 Shorted or sticking button Clean button or replace touch pad
F8 Defective ERC Replace ERC
F9 Door Latch Error Check latch


The following diagnostic chart Does not apply to Whirlpool 'Y' line products. If the model number contains a Y near the end of the number, DO NOT use this chart.
Whirlpool / KitchenAid / Roper
Oven Fault Codes
Ovens with 4 digit displays
Display Condition Remedy
F0-E0 Analog to Digital failure Disconnect panel for 30 seconds. if error re-appears then replace control
F1-E1 Defective ERC Replace ERC
F2-E0 Shorted Keypad Replace Keypad
F3-E0 Sensor or Sensor Fuse Open Replace Sensor or Fuse
F3-E1 Shorted wire or Sensor locate short and correct it or replace Sensor
F3-E2 Oven over heat Replace Sensor
F3-E3 Cleaning Temp over heat Replace Sensor
F5-E0 Door Error Check Door
F5-E1 Door Latch Check Latch
F5-E2 Door Switch Check Switch
Ovens with 2 Digit Displays
F0 Defective ERC Replace ERC
F1 Defective ERC Replace ERC
F2 Oven over heat Replace defective Sensor
F3 Oven Sensor Open Check/Replace Sensor
F4 Shorted wire or Sensor locate short and correct it or replace Sensor
F5 Defective ERC Replace ERC
F6 Problem with time keeping circuit Reset Time or cooking operation and check for proper ground
F7 Shorted or sticking button Clean button or replace ERC
F8 Defective ERC Replace ERC
F9 Door Latch Error Check latch and latch circuit


If you need further help, reach me via phone at https://www.6ya.com/expert/dan_73bbd84fe1d95b61

pulse F1(CALC), F1(1VAR) and it goes to 1-Variable Screen and shows the following:
x-(mean): 49.3333333
Sumx:296
Sumx^2:15066
xon:8.78761755
xon-1:9.62635271
n:6

I guess that you wanted the x- and xon

Also are available in RUN mode through VARS, F3(STAT), F1(X), F2(x-) and F5(xon)

Clear the ram:
1. Press [MENU]2. Press [tan] (MEM)3. Select RESET4. [F1] (yes)