Headlights

My wife's LS430 will cut the lights immediately when I press the lock button on the fob, twice. (maybe once, I can't recall).

Although it seems kinda' silly to lock the car while rousting around in the truck, you might try that.

I tried that this morning after food shopping. While pressing the lock button on the fob twice usually turns off the lights, this time it did not.

So, I still have a problem where I would like to have the lights go out when the trunk is open.

Make sure your headlight switch is in "auto" to turn off the lights immediately with two presses of the lock button on the key fob. Also, check the headlight operation section of your owner's manual. The lights should stay on for 30 seconds AFTER YOU OPEN YOUR DOOR (it has nothing to do with closing the trunk). If there is an asterisk which says words to the effect, "this setting can be changed - see your Lexus dealer", you can ask them to change it so the lights go off immediately after you open your door.

I will say, at least on our 430, you're correct the lights will remain on for some # of seconds(presumably 30) after exiting the vehicle.

UNLESS.... You leave a door ajar. Then apparently, the lights will remain on indefinitely. I don't know if this ajar condition applies to the trunk.

It seems like every time something unexpected happens with this car, I'm digging through a ~500 page owner's manual.