Lexus LS460 2011 Owner's Manual page 697

4-3. Do-it-yourself maintenance
STEP 4

If the electronic key battery is discharged
The following symptoms may occur:

The smart entry & start system and wireless remote control will not
function properly.

The operational range is reduced.

Use a CR1632 lithium battery

Batteries can be purchased at any authorized Lexus dealer or repairer, or
another duly qualified and equipped professional, jewelers, or camera
stores.

Replace only with the same or equivalent type recommended by the
manufacturer.

Dispose of used batteries according to the local laws.

When the card key battery needs to be replaced (if equipped)
The battery for the card key is available only at Lexus dealers. Your Lexus
dealer can replace the battery for you.
662
LS460_EE
Remove the depleted battery.
Insert a new battery with the
"+" terminal facing up.