Texas Instruments TI-89 Calculator "reset cr1620" Questions

reset (hold simultaneously Left + Right + 2nd + On). If it just isn't wanting to display properly, but does turn on, that might help. I think you can do the same thing by taking the four AAA's out and

CR1620 ENERCELL brand battery. Still, only a black line across the screen when I turned on the calculator. There was a small anount of white, powdery residue in the battery compartment. I think it may

...cr1620 lithium battery and the 4 AAAA batteries work.  Also ensure that you've attempted to clear out all the memory and reset the calculator.  To delete all variables, tables, graphs, ...

...CR1620 battery. Any suggestions? TI calculators have an annoying habit of dimming the screen when the batteries are changed so that it appears as if the calculator isn't turning on. Turn the ...