Education Technology

Solution 11845: Resolving the Error Message "Illegal Instruction" on the TI-89 Family, TI-92 Family, and Voyage™ 200 Graphing Calculators.

How do I resolve the error message "Illegal Instruction" on the TI-89 family, TI-92 family, and Voyage 200 graphing calculators?

The error message Illegal Instruction on the TI-89 family, TI-92 family, and Voyage 200 is caused when a third party shell program tries to overwrite the pre-programmed code of the calculator. To resolve this error, the calculator will need to be reset in order to remove all third party programs that may have contributed to the issue.

Please, bear in mind that this will erase the memory of the calculator and restore all manufacturer's defaults. **(USE BRAND-NEW BATTERIES)**

Resetting the TI-89 family:

• Hold down the following keys: [2nd] [<] and [>] (right and left arrow keys).
• Press [ON].
• Release all keys simultaneously.

Resetting the TI-92 family and Voyage 200:

• Press and hold [2ND].
• Press and hold [LOCK] (the little hand).
• While holding both, press [ON].
• Release all keys simultaneously.

If this procedure does not restore the unit, remove a battery and press [ON] for 30 seconds. Replace the battery, turn on the unit, and adjust the contrast.

If you require additional assistance please contact TI-Cares.