Cavedog

Just traded up for an LS460. It of course has TPMS the old LS430 did not. Tire pressures was way out of whack. Three had pressures over 50psi one at 26psi and spare at 36psi. I set all at 33psi with an accurate digital gauge. I reset the TPMS with the button below the steering wheel. The multi display did not show any tire pressures. The multi dispay was and is blank. Went for a drive yesterday of 100 miles, got no reset or multi display.
What could be wrong, all sensors dead and why no multi display? Any suggestions before I have to humble myself at the dealer.

jmcraney

I bet it rides better since you let some air out.

All of your wheel sensors may be out, but that is unlikely.

It may be that the wheel sensors are not registered in the car. Electronic tools are required to check or fix that.

Many tire dealers are equipped with the electronic tools and knowledge to help you resolve this and many will help you without charge. Try Costco,Walmart,Sam’s Club, Discount Tire and others.

colfax

you are at basically sea level so whatever your hand psi gauge says should be about the same as the car display
Lexus recommends on the side of the door, 35 for all four and the spare

I set mine at 37, I like a little firmer ride and a higher psi than 35 so more time until air slowly leaks

if I were you I would reset the psi to 37 and then with the car in park and ignition on but not motor on
push and hold the little button in for a while until you see the display reset to no psi showing

I just did this yesterday and when I went for a drive the psi display began to show after less than 1/2 mile or so

lwphat66

I 2nd colfax's reply. My manual states that the tire pressure warning reset switch should be held down for at least 3 seconds. What was the display reading before you adjusted pressures and pressed the switch? Have you pressed the DISP button (cycles thru the different displays) on the right side on the steering wheel? Also, are the wheels OEM or aftermarket?

jmcraney

The switch that you seem to be referring to is not a "reset" switch. It is a Benchmark Set switch. Benchmarking is the process of establishing the TPMS low pressure warning thresholds. When the switch is pressed, all 5 tire pressures are benchmarked simultaneously and independently. Operation of the switch has nothing to do with the display.

Kuhan

I agree. I think the TPMS might not be registered. If that’s the case, wouldn’t the car display a flashing warning though.

The tool I used was a Carista to register new TPMS. But tire shops should be able to diagnose it quickly.

lwphat66

Yes, it's one and the same. As you stated, it is used for benchmarking (provided the TPMS sensors have been initialized/relearned). My manual calls it a "Tire Pressure Warning Reset Switch", not a benchmarking switch, and that is the reason I referred to it as such. The only times I have a blank center screen is when I opt to via the DISP button. I just went thru having the ECU relearn the new TPMS sensors when I installed new wheels and tires. At that time, displayed was a combination of no psi readings and old readings from the previous sensors. With my Autel TS508, I activated all the new TPMS sensors and had the ECU relearn them (including the spare). Now I have no more tire pressure warning light, and my psi displays in the following top-down order: LF, RF, RR, LR, spare.

The psi display is nice to show any significant changes, but I still check every tire manually at least once a month....but that's just me.

Dave144239

Did you just scroll away from the TPMS display? If so, press the DISP button on the steering wheel until the TPMS display comes back.

jmcraney

The TPMS was new in the '07 model and the manual was indeed vague. They did use the term "reset" when referring to the benchmark SET switch. Much more detail and clarity was included in subsequent year manuals but the function of that switch and benchmarking has continued to be confusing to many.

Here is a clip from the '07 manual:

lwphat66

Cool, thanks! Those pages are exactly what I was referring to when resetting the benchmark using the tire pressure warning reset switch.

jmcraney

I sense you know this but in case you don't, the '07s didn't have a TPMS localization feature and there is no significance to the pressure display order. I know you will enjoy your car. I had a new '07 and except for the wind noise problem, which was easily fixed, it was a wonderful experience. And, the TPMS has been one of the most reliable and much appreciated safety features of any car I have owned. The Lexus implementation of the TPMS mandate is solid.

lwphat66

Yeah, tell me about it....trying to figure out the randomness of the readings when I first started working on the car kinda dumbfounded me. That's why the Autel is so nice, it reads/relearns the TPMSs into the ECU in that order (I verified via manual testing, so I know LF, RF, RR, LR, spare is the sequence now). Your wind noise fix is saved in my favorites and is on the list of things to do (near the top). Props to you and many thanks for the detailed write-up!

colfax

Ok, so if the TPMS is for setting the PSI that the low psi warning light comes on...

then why when I set all four tires at 35 psi on the display and then do the button, why does the light NOT come on when
the pis display goes down to 34, 32, and comes on only at 30?

this explanation does not make sense to me......

lwphat66

Years ago I experienced the same thing and recall the low warning threshold to be 30-32 psi (I don't remember the exact psi). As on pg. 512 above, the manual states only two reasons to initialize the tire pressure warning system, and neither has to do with low tire pressure. This page is the only place in the manual (regarding tire pressure) where I've seen the word "benchmark" used, and I take it to mean calibration, setting, or the like. I don't plan to press that button unless it's a last resort sort of deal. To me, the TPMS display is a more of a convenience feature (like a low fuel warning light), so I will not rely on it solely to let me know the psi of my tires.

R Z

Seems to me there is an adjustment for how low the tire goes before the light comes on. Not sure it that's with 07-12.