Toyota vehicles come with either a smart key system or a standard remote. The standard keyless entry remote is integrated with the ignition key. The smart key system uses an "Engine Start" button. Every couple of years, you may need to replace the battery in your smart key or in your standard keyless entry remote. The battery replacement procedure is similar for the two key systems, with only slight variations. Use only the listed battery type; no other batteries are compatible. The key system equipped in your vehicle depends on which Toyota model you have.
Grasp the end of the smart key and pull out the mechanical key. Hold the smart key in your hand with the "Toyota" emblem facing up. The cross in the logo should be facing away from you.
Insert the flat head screwdriver into the slot on the bottom right edge of the smart key. Turn the screwdriver gently to pop off the cover. Lift the cover off fully. You'll see the battery.
Pull the battery out of its holder. Lay the new battery in the holder. The "positive" side must face up.
Place the cover back on top of the smart key. Push the cover down firmly to reattach it.
Insert the mechanical key back into the smart key.
Turn the keyless entry remote over. The "Toyota" logo should be facing up. The key end of the remote should be facing away from you.
Insert the flat head screwdriver into the edge of the key chain holder. Turn the screwdriver to open the keyless remote. Set the cover aside.
Grasp the keyless entry module and lift it up. This is the "computer" part of the remote. The battery is inside this module.
Grasp each end of the module and pull apart to open it. You'll see the battery. Lift it out of the holder. Insert the new battery. The "positive" side should be facing up toward the module cover with the arrow on it.
Push the two ends of the module back together. They will snap into place. Insert the module back into the keyless entry remote. The arrow on top of the module should be facing up.
Place the cover back on top of the keyless remote. Push it down firmly against the unit to snap it back together.