Probability and Statistics Index > TI-89 for Statistics Topic Index > TI-89 Error Codes

The TI-89 can be a frustrating gadget. Even if you follow the steps in the TI-89 articles perfectly, you may get an unexpected **TI-89 error code**, like “Undefined Variable.” Usually, you’ve typed something in wrong or there’s a setting somewhere on the calculator that’s preventing it from performing whatever function you want it to perform. This is a list of the most common codes you are likely to encounter.

## Common TI-89 Error Codes

Problem: **“Undefined Variable”** error. Solution: Double check your inputs any look for typos. If that doesn’t work, reset the variable memory. Press

2nd 6 f1 ENTER. Select “2:Default” and then press ENTER twice.

Problem: **“Syntax Error”**. Solution: Check you have included parentheses “(” “)” to open and close your arguments.

Problem: **“Argument Error”**. Solution: If you get this error when trying to enter a function from the graphing list in the home screen entry line, make sure you are referring to the function by the correct number and that you have a function entered in the right place in the y=editor.

Problem: **TI89 will not graph, or graphs too many functions**. Solution: Check the y=editor to make sure only the functions you want to graph are turned on (look for check marks to the left). To remove (or add) a check mark, scroll to the space the the left of the “y=” and then press the f4 key next to any function you want to graph (or not to graph).

Error not listed here? Check Appendix B of the 8992bookengfor more TI-89 Error codes.

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I followed the steps to reset the TI-89 to default setting and I am still getting the ERROR Undefined variable when trying to graph a scatter plot using stats/list Editor.

Ronni,

This could be a few different things. Have you reset your variable memory?

• Press [2nd] [6] (MEM) [F1] [ENTER]

• Select 2:Default

• Press [ENTER] and Defaults Set is displayed

• Press [ENTER]

If that doesn’t work, are you using the multiplication symbol on your y=? Have you tried going to home, F6 and clean “clear a – z”?