Toyota Highlander key fob battery

Separate remote fob

1. The remote is a small standalone unit. You will not need to touch the ignition key at all.
2. Find the slot along the edge and turn a coin in it. Go slowly so the clips do not snap.
3. Replace the cell, keeping the + side where it was, and check the small metal tab still touches it.
4. Reassemble and test from a short distance.

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.

Key with remote in the head

1. This type has the buttons built into the key head. The cell is inside that head, between two clipped halves.
2. Find the seam around the head. Twist a coin or small flat screwdriver in the notch at the blade end or side until the halves part.
3. Replace the cell with the same face showing, and make sure the rubber keypad sits flat before closing.
4. Press the head together until it clicks and test the buttons. The transponder chip that lets the car start is separate from the battery, so starting should not change.

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.