I added enough air to the tires to 34psi and the tire yellow light went off as did the yellow triangle light so yes it was the low air pressure. I did not recall this triangle light being on when I was low on tire pressure, I thought only the tire yellow light came on.

I find the tire pressure on my Lexus to be easily dip from the 33 psi to around 30psi when the light comes on my other vehicles with this feature did not seem to have a preferred running air pressure so close to the trigger point for the low warning. I see this light a few times a year here in N. Texas and it always comes in when I make the trip to NM mountains.

 

Johnw2 - Some tires tend to leak air more than others. I've found the Pirellis tend to hold air pretty well.

 

Thanks, I have my second set of tires on my LS, they are Pirellis but pzero nero rather than the ones recommend on here. I ran into tire issues right before a road trip to NM mountains and took the Pirellis the dealer had as not time to ship a set in. Hard to imagine to me but no one seemed to have that version in stock and it had to be shipped from Shreveport. I like these tires fine they are quiet and too early to tell about wear.

 

And if the above steps don't do the trick for some reason, I found this mini-procedure (that includes turning off an oil change notice if it appears on your navigation screen):To reset the oil maintenance data on the instrument panel you must:
1. Switch the display to trip meter "B" while the engine is running.
2. Turn the engine off.
3. While pressing (and holding) the trip meter reset switch, press the engine start button twice (foot must be off the brake pedal).
4. Continue holding the trip meter reset switch until the display goes from "Resetting Oil Maintenance Data" to "Complete."
5. Press engine start button to turn off the vehicle.

To turn off the oil maintenance "reminder" from the navigation screen you must:
1. Press the "Menu" button above your remote touch controller.
2. Select "Setup," then "Vehicle," and then "Maintenance."
3. Select "Reminder" at the top of the screen to disable all maintenance reminders.*

*Unlike the maintenance data on your vehicle's instrument panel, the dealer typically does not reset the maintenance reminders on your navigation display. This is customizable by the vehicle owner and works similar to a calendar for individuals who prefer to do their own maintenance. All actual maintenance data, warnings, and reminders will be displayed on the instrument panel."