Toyota Corolla key fob battery

Remote key (form not stated in the source)

1. The form of the remote is not named in the source for these years.
2. Look for a notch, slide or screw on the case. A coin or small flat screwdriver, twisted gently, opens most fobs.
3. Swap the coin cell, keeping the same face showing, then make sure the doors respond.

No battery to replace for these years, per the source shown.

Separate remote fob

1. A separate fob has no key blade inside, so it opens with nothing but a coin or a small screwdriver.
2. Find the slot along the edge and turn a coin in it. Go slowly so the clips do not snap.
3. Swap the cell or cells, keeping the same side up as the old ones.
4. Snap the case shut and watch for the lights to flash when you press lock at the car.

A CR2032 is 20 mm across and 3.2 mm thick. CR2032, CR2025 and CR2016 share the same width but not the same thickness, so a swap between them can leave a loose contact or a case that will not close.

Key with remote in the head

1. Here the key blade and remote are one piece. You open the plastic head, not the blade.
2. Many key heads split along the side seam. Start at the small notch and pry a little at a time.
3. Replace the cell with the same face showing, and make sure the rubber keypad sits flat before closing.
4. Snap it closed and press each button. The car still starts with a dead remote battery on most of these keys, because the start chip needs no battery.

A CR2016 is 20 mm across and 1.6 mm thick. CR2032, CR2025 and CR2016 share the same width but not the same thickness, so a swap between them can leave a loose contact or a case that will not close.

A CR2032 is 20 mm across and 3.2 mm thick. CR2032, CR2025 and CR2016 share the same width but not the same thickness, so a swap between them can leave a loose contact or a case that will not close.

Smart key (push-button start)

1. Most push-button fobs hide a metal backup key. Press or slide its catch and draw the key out first.
2. Look inside the empty key slot for a notch. Put the tip of the metal key or a small flat screwdriver wrapped in tape there and twist gently until the shell splits.
3. Pop the old battery out with a toothpick or plastic pick, not a metal blade, and seat the new one with the + side matching the old one.
4. Close the case until it clicks all the way round, put the metal key back, then try the buttons and a push-button start.

On most Toyota smart keys the metal key slides out after you press a small release, and the case opens at the slot it leaves behind.

A CR1632 is 16 mm across and 3.2 mm thick. It is easy to confuse with the 20 mm CR20xx sizes, which will not fit.

A CR2032 is 20 mm across and 3.2 mm thick. CR2032, CR2025 and CR2016 share the same width but not the same thickness, so a swap between them can leave a loose contact or a case that will not close.

A CR2450 is 24.5 mm across and 5.0 mm thick, much fatter than a CR2032. A thinner cell will rattle and lose contact, so buy the exact size.