Snarky

Does anyone know how the wireless tire sensors on the GX470 work ?
Are they inside the wheels themselves or can you put non-Lexus custom wheels on a GX470 ?

Thanks for your help!

rxdriver

They're part of the valve stem, inside the tire. It is possible to get aftermarket wheels that have room around the valve stem to accept the sensor, but of course you have to ask explicitly. Some aftermarket wheels also come with "compatible" pressure sensors, so that's also an option. But if you go with new sensors, you'll have to take the truck to the dealer to have their ID's registered with the computer after they're installed.

The sensors transmit pressure and temperature information at regular intervals from all 5 tires. (If the light comes on for no apparent reason, check the spare!) The light will come on if the pressure drops below approximately 27 psi.

CVsIS250

You can put any wheel you want on the Lexus. You don't have to use the tire sensor system if you don't want to. Since they are located in the valve stem, you can have them re-installed in any tires.

PS, if you have a problem with one, it can cost $100 and some change to get it fixed.

CV

puddintane

My tire pressure warning light came on last week; all tires OK; Lexus told me hat it will come on in cold weather because of reduced air pressure in cold tires; It goes off after driving awhile BUT it is supposed to warn of low air pressure, not be a temperature warning. One, I guess, has to inspect the tires every morning
if the light is on, in case it is a real problem

puddintane

llcc1975

If you didn't put them into the aftermarket wheels, wouldn't you then have to live with the annoynig tire pressure low warning light in perpetuity?

loflin

It IS warning of Low Pressure. Pressure varies with Temp. The setting they chose to register a warning (26 or 27 PSI, I believe), should NOT register a warning if your tires are properly inflated, even in the winter.

Check your tire pressure (with a tire gauge) in the cold morning. Bring pressure up to at least 29 or 30 psi (recommended is 32 PSI).

Then you shouldn't get the warning, anymore.

rxdriver

I think Lexus would argue that 27 psi is not properly inflated.

If they're getting below 27 psi outside, then you have to adjust for that when the truck is sitting in the warm garage. If the garage is 40 degrees warmer than the outside air, then you'll want to add 4 psi to whatever you consider to be normal pressure. Then they're over-inflated in the warm garage, but correct outside in the cold air.

CVsIS250

No, pull the fuse! I would imaging that you can disable it.

CV

bigbwb

I have a similar issue. I drive a 2006 4runner and my fiance drives a 2006 IS250awd and today, both are TPMS lights came on. I have called both related dealers and they had several conflicting suggestions. The toyota dealer suggested I over-inflate the tires by 10psi and bring them back down and the light will turn off, and for the IS, Lexus said to check for a reset switch under the dash or try checking for proper inlfation. Today in WI, we had some real cold weather that started this problem.

Any suggestions or advice?

Thanks,

Brandon

rxdriver

The light comes on when any tire drops below 27 psi.

The bit about overinflating them and then dropping them back down comes from the initial "wake-up" process for the sensors when they are new. On vehicles made in Japan, the sensors are in a battery-saving mode and must be activated in a manner similar to what was described to you. But this can only be the problem if the light is flashing. If the light is on solid, a tire is low.

The reset button may apply to more than one Lexus model, but the only one I know of for sure is on the RX350. The button allows you to set the warning level to something other than 27 psi. You can set the tires where you want them, and then calibrate the system with the button. Then the system will tell you when the tires drop a few psi below that setting.

Given the cold temps this morning in the midwest, the most likely problem is that one or more tires (check the spare!!) dropped below 27 psi in the cold.

bigbwb

Thanks rxdriver,

The light in my 4runner came off this morning after putting air in last night. I will put some air in the IS250 tonight to see if that works also.

Brandon

Capirato

Can I assume that a signal is sent to a receiver which turns on the warning light when one or more tires have pressures of less than 27 lbs ??

Then you can remove the five tires to a distance where the signal is not received by the receiver ??

If so, when installing aftermarket tires with no sensors, should not turn on warning lights.

Any opinions ??

~ Cap

The G Man

I think if you remove any of the tires to a distance where the signal is not received by the receiver, the warning light will come on.

rxdriver

That's right - if the system isn't getting readings from all 5 sensors, it will make the light flash indicating a malfunction.

Capirato

They eliminated the flashing light on the GX.

2004 GX470 TIRE PRESSURE WARNING SYSTEM

When the tire pressure warning system detects that a tire inflation pressure becomes lower than the threshold (185 kPa, 1.9 kgf/cm². 26.8 psi), it will turn ON the tire pressure warning light to warn the driver.

This system can register main (normal) and 2nd (winter) tire sets in the tire pressure monitor ECU. The main or 2nd tires can be selected by pressing the tire select switch.

The tire pressure monitor receiver receives the tire inflation pressure and the tire inside air temperature from the signals of five tire pressure sensors (including the spare tire) and transmits to the tire pressure monitor ECU.

The tire pressure monitor ECU monitors the tire inflation pressure and detects the low tire inflation pressure.

~ Cap