HS with Remote Start -- can't get it to work
 

I have an HS with the "remote start" option.

From what I understand, to remotely start the car, you push the "Lock" button on the remote three times in succession, while holding the 3rd press for 3 seconds.

Anyway, I've tried this over and over, to no avail.

Am I missing something?

You have to push the lock button down 2 times and hold the third time till you see the lights flash.Release.
Should start a few seconds after.At least that's how the factory remote start works on my RX.Should be the same on other Lexus models.
Although,a hybrid may be different.

Within 2 seconds quickly - to close, close, close more than 3 seconds!

I click mine a few times quickly and hold the lock button on my 450h. Like Joeb said, after holding the lock button for a few seconds the lights will flash several times to indicate it started. Remote start is supposed to work up to 75 feet but I find it to be shorter than that. I did start it at a greater distance than that once though.

I'd try it with the other remote to see if a new battery is in order. I'm not sure how quickly they get depleted now. I have replacements on hand just in case. Good luck.