Texas Instruments TI-89 Manual Book page 594

Replacing the
Alkaline Batteries in
the TI-89
Replacing the
Lithium Battery in
the TI-89
is on, turn it off (press 2 ®) to avoid loss of
1. If the
TI-89
information stored in memory.
2. Slide the protective cover over the keyboard.
3. Holding the calculator upright, push down on the battery cover
latch, and then remove the cover.
4. Remove all four discharged AAA batteries.
5. Install four new AAA alkaline batteries, arranged according to the
polarity (+ and -) diagram inside the battery compartment.
Lithium battery
6. Replace the battery cover by inserting the two prongs into the
two slots at the bottom of the battery compartment, and then
push the cover until the latch snaps closed.
To replace the lithium backup battery, remove the battery cover and
unscrew the tiny screw holding the BACK UP BATTERY cover in
place.
Remove the old battery and install a new
positive (+) side up. Replace the cover and the screw.
Appendix C: Service and Warranty Information
AAA alkaline
batteries
or battery,
CR1616 CR1620
577