I have a 2005 LS430 with the smart unlock (where when you grab the door handle it unlocks automatically). For some reason, only the passenger front and drivers rear doors work with this. I've checked the under-dash button and it's fine, and my keyless ignition works. But when I grab the drivers door it will not unlock. Is this a wiring issue? Fuse? Broken handle?

Thanks!

 

If it works for the rear drivers side door but not for the drivers door, then it must be an issue with either the drivers door handle or else with the drivers door ECU.
Other than that, not sure how you'd troubleshoot it, but hopefully someone else knows how.