Toyota VIOS Owner's Manual page 482

 Vehicles with a smart entry & start system
1 Remove the cover.
To prevent damage to the key,
cover the tip of the flathead screw-
driver with a tape.
2 Remove the battery cover.
Pull the knob of the battery cover
to remove.
3 Remove the depleted battery.
Insert a new battery with the "+"
terminal facing up.
For Taiwan
VIOS_OM_GE_OM52L06E(TMT)_OM99V20b(TDB)_OM52L61E(TMP)_0D053(IMC)
7-3. Do-it-yourself maintenance
Knob
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