Nearly all new Toyota vehicles come with a keyless entry remote. This small remote attaches to your key chain and can be used to unlock and lock your car, in addition to activating the panic alarm. Some keyless models even allow you to pop your boot with the push of a button. However, the remote runs on a battery, which will eventually run out of power and need to be changed.
Look at the front of your keyless Toyota remote; you will see a small indentation in the plastic. This small hole allows you to open the remote.
Insert a key into the indentation and pull upward. The remote is going to separate into two different pieces.
Remove the thin, circular battery by pulling it up. You may need to use your key to pry it out.
Insert the replacement 3-volt battery. On the inside of where the battery is inserted you can see a symbol for either a positive or negative side (depending on what side of the casing you are looking at). Place the negative side of the battery down onto the negative side of the remote (there are corresponding minus and plus signs on the battery).
Snap the two parts of the Toyota keyless remote back together and you are set to resume using it.