Corolla Axio NKE165 Hybrid Key Battery: CR2016 or CR1632?

Toyota's May 2016 Axio Hybrid owner manual gives CR2016 for a standard remote without Smart Entry & Start and CR1632 for a Smart Entry & Start electronic key. Check the equipment and physical transmitter first; these two coin-cell types are not substitutes for one another.

Work on a clear dry surface, keeping replacement cells and removed parts out of reach of children. Toyota warns that swallowed batteries and small transmitter components are dangerous. Protect a screwdriver's tip with a cloth to limit scratches.

Use the protected flat screwdriver to release the outer cover while keeping the buttons facing downward, as Toyota instructs, to reduce the chance of loose buttons coming out. Remove the internal transmitter module without tugging its circuit components.

Toyota shows a coin or suitable tool releasing the module cover. Remove the exhausted coin cell, fit a new CR2016 with its positive (+) face pointing up, and reverse the module-cover and outer-cover removal sequence without bending battery contacts.

Release and pull out the electronic key's mechanical emergency key. Use a cloth-protected flat screwdriver to open the electronic housing at its designed opening; avoid prying against the circuit board or breaking the case tabs.

Toyota notes that the electronic module can adhere to the upper cover and conceal the battery. If so, gently turn the module to expose the cell as illustrated in the manual. Remove the spent battery and install the new CR1632 with its positive (+) face upward.

Refit the inner module or cover and any removed mechanical key in reverse order. Confirm the case closes flush, then test lock/unlock and the vehicle's matching key-recognition function. A damaged or different transmitter should be checked by a qualified technician rather than forced.