Interapid

I like the screen where it shows the tire pressure of each tire. Is the car smart enough to know which tire is where? If I rotate the tires myself can it figure that out?

Htony

Sensor has it's own id. So Tech Stream will show where the wheel/tire is mounted.

Interapid

Yes but if I switch the left rear to the left front will the car know that or does something have to be entered?

lesz

This is from page 442 of the 2017 ES manual (exact page may vary for other ES model years).

"The tire pressure warning system must be initialized in the following circumstances:
● When rotating the tires.
● When the tire inflation pressure is changed such as when changing traveling
speed or load weight."

This would seem to indicate that you need to re-initialize the TPMS after tire rotation to have the multi-information display show the pressures for the proper tire locations.

Initialization is done with a button below the left side of the dash.

Htony

Nothing to change as long as pressure is not changed. It'll be just business as usual.

lesz

What you are saying does not seem to be consistent with the part of the ES manual that I quoted above.

In any case, re-initializing the TPMS takes only a few seconds, and doing it isn't a big deal.

mcmike522

FWIW, with my GM vehicles there were 2 ways to program the TPMS's.
1. Go around to each tire with a special electronic tool to program the tires - I think every tire shop should have one of these tools.
2. There is also a special sequence to manually program each tire using the drivers controls with vehicle parked. I had to search the web to find the special sequence for my Chevy Malibu.

Htony

Reset is just to set the threshold of the pressure. Lexus needs to relearn the id of new set of sensors by it's id. If the pressure of new tires are same as previous set there is nothing to change.
After replacing tires with same pressures deflate one tire it'will get TPMS low pressure warning. I use Autel TPMS handheld tool. After tire replacement using this tool; I trigger, scan each sensor's
id. pressure, temperature and battery status. The 4 ids. are stored on a scratch pad of the tool. Then connect the tool to OBD port which will bring up a question 'want to store new ids.? Yes then it's
done. less than 30 mins. job. If you use Tech Stream you have 5 secs. to enter 4 ids. If not you have yo repeat until 4 ids. are entered in 5 secs. In this case using copy and paste command is easier.

lesz

But nothing in your explanation deals with why you are saying that the system does not need to be re-initialized after a tire rotation even though the manual says "the tire pressure warning system must be initialized in the following circumstances:
● When rotating the tires".

Interapid

The car knows what the tire pressure is. Thats not the problem. I need to know if the car knows what tire is on what corner.

Htony

I doubt ECU tracks the position of individual tire which has it's unique sensor id. I don't think we don't need to know that. Only way is using TPMS trigger/scanner tool.

Htony

Procedure using Tech Stream or other tool = initialization? Owner's manual is not a service manual. Try either method yourself and see if it works without pushing reset button.

lesz

That is not correct. Techstream or other programing tool is necessary for registering the TPMS, but it is not necessary to re-initialize the system. To re-initialize the system, you only need to press the button/switch under the dash, and that is what the manual says you need to do after a tire rotation.

Also, from page 444 of the 2017 ES manual:
"Do not fail to initialize the tire pressure
warning system after tire rotation."

Also, from page 444 of the 2017 ES, manual, here are the instructions for re-initializing the TPMS:

"How to initialize the tire pressure warning system
Park the vehicle in a safe place and turn the engine switch off.
Initialization cannot be performed while the vehicle is moving.
Adjust the tire inflation pressure to the specified cold tire inflation pressure
level. (→P. 522)
Make sure to adjust the tire pressure to the specified cold tire inflation pressure
level. The tire pressure warning system will operate based on this pressure level.
Turn the engine switch to IGNITION ON mode.
Press and hold the tire pressure
warning reset switch until the tire
pressure warning light blinks
slowly 3 times.
Wait for a few minutes with the engine switch in IGNITION ON mode and
then turn the engine switch off."

So, even though the manual clearly says multiple times that, after a tire rotation, you need to re-initialize the TPMS and, even though the manual spends 3 pages explaining about re-initializing the TPMS, you seem to be saying that the manual is wrong. Considering how simple it is to re-initialize the TPMS, I think I'll chose to believe that the manual is correct, and I'll take the few seconds necessary to do the re-initialization after tire rotations.

Mike728

My understanding is that the car will know where the tire is after a rotation without any extra steps. The sensors are registered to the vehicle, so as long as they're not changed, all is good. There are receivers located near each corner that speak to the sensors, thus no reprogramming is necessary. Re-initializing the TMPS, as the manual states, probably just polls the system, so the update is performed then.

Interapid

Thanks Lesz, I plan on taking your advice (the manuals) But first I think I will run a simple test and get back to the forum. I just rotated the tires last week. I am going to take the left rear and fill it to 45lbs and see what the left rear dash readout says. Just a quick test to see if it works.
Mike728, I hope your right but we will see!
Thanks guys.