Video by Carolina Cowboys Open on YouTube ↗
The short version
Smart key gone completely dead after sitting unused? Pop the shell open and swap in a fresh CR1632 battery — no reprogramming needed.
- CR1632 replacement batteries Duracell recommended in the video for the printed freshness date. Check price
- Replacement smart key (if the old one won't come back) Check price
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A Lexus smart key that’s been sitting in a drawer for a few years will go completely dead — no beep, no lock response, nothing. Before assuming it’s shot, it’s almost always just the battery.
Replacing the Battery
- Open the key shell. Take the metal valet key (it’s stored inside the fob) and fit it into the small notch on the edge of the shell, then twist. The shell pops open.
- Swap the battery. It takes a CR1632. The video uses a Duracell specifically for the printed date code, so you know the cell is actually fresh rather than old stock.
- Close it up and test. Snap the shell back together and check the door lock — in this case it worked right away with no resync or reprogramming step required.
That’s It
If the fob still doesn’t respond after a fresh battery, the fob itself (not just the battery) may have failed — a replacement smart key is linked above.
Questions people ask about this job
Do I need to resync the key after changing the battery?
Not in this case — after the battery swap, the door lock worked immediately with no resync step needed.
Keep going
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