iomair

I have like these sensors inside the tires

Sasnuke

ok...those are the same as mine. If you have these and your LED display doesn't display the individual pressure, then I don't think there is anything you can do.

iomair

So I can't do anything with it ? Also I can't program it? Maybe It just on and off in the car computer?

Sasnuke

The way the IS detects the position is the vehicle has a sensor mounted on the left front and the right rear of the body of the vehicle. The left front sensor detects the left side TPMS sensors, and the right rear does the same for the right side.
If the vehicle doesn't have these two sensors, then the vehicle cannot tell you which tire has what pressure.
The tire sensors are programmed to the car, but it seems your IS has the same system like my Highlander. The Highlander cannot detect position so it doesn't show pressure. It only has the warning light.

iomair

What about if I buy like your sensor can I install it? If the answer is yes , how ?

Sasnuke

Here is some information on the system. To correct myself above, the sensors on the body that detect the tire sensors are both on the left side of the vehicle...see #7 and #8 below.
I'll look for something that will show you where the sensors are. You can check you IS and see if the sensors are there. If you don't have the sensors, then you need to check to see if you have the harness connectors for the sensors.
If you don't have the harness connectors, then there's no point going further.

DESCRIPTION OF SYSTEM

(a) When the tire pressure warning system detects that the tire pressure of a tire is lower than the threshold, it will inform the driver using a warning light.
(b) The tire pressure warning ECU and receiver receives the transmitter ID, temperature and tire pressure information from the tire pressure warning valve and transmitters shown in the following illustration. This information is used to determine when the pressure in one of the tires has dropped.


*1
Tire Pressure Warning ECU and Receiver
*2
Tire Pressure Warning Valve and Transmitter
*3
Combination Meter Assembly

- Tire Pressure Warning Light
*4
Main Body ECU (Multiplex Network Body ECU)
*5
Tire Pressure Warning Reset Switch
*6
Tire Inflation Pressure Display Function:

Tire Pressure Monitor Initiator Driver
*7
Tire Inflation Pressure Display Function:

Front Tire Pressure Monitor Initiator
*8
Tire Inflation Pressure Display Function:

Rear Tire Pressure Monitor Initiator
*a
Front
*b
Tire Inflation Pressure Display Function:

Tire Position Identification Signal
DESCRIPTION OF TIRE POSITION IDENTIFICATION FUNCTION (Tire Inflation Pressure Display Function)

(a) The deterioration of signal strength at a distance (when a transmitter is close, the signal is strong, and when a transmitter is far, the signal is weak) is used to determine position. Position identification is performed when the engine switch is turned on (IG), when the vehicle starts moving (if the position could not be determined when the engine switch was turned on (IG)), when initialization is performed and when ID registration is completed.

For front position identification (rear position identification is performed in the same way):

1. The front tire pressure monitor initiator sends a position identification signal to all of the tire pressure warning valve and transmitters.
2. The tire pressure warning valve and transmitters respond to the received position identification signal by sending a signal to the tire pressure warning ECU and receiver indicating the strength of the received signal.
3. HINT:The strength of the signals is different because the distance between the front tire pressure monitor initiator and each tire is different.
4. The tire pressure warning ECU and receiver receives the signal strength information signals from the tire pressure warning valve and transmitters and associates them with their correct position based on the received information.

Sasnuke

Here's the front one...

Here's the rear one...

Matroushi

I have a 350 F Sport GCC spec. It DOES have TPMS and it works, the only thing is that the display that shows the tire pressures is not there.
I think its just a feature in the display that Lexus decided to skip over. I doubt the car is missing any sensors or else the system wouldn't work.

Sasnuke

Thanks for confirming...so it looks like a market specific feature that was omitted.
It would be interesting to know if the vehicle has the two sensors on the left for detecting the position, because if it does, then it's just the display that's not showing it.
If the sensors are not there, then the TPMS system is using one receiver that detects all 4 sensors, and therefore cannot tell position.

Matroushi

I think you are correct about using one receiver. In the 'caution' box under the Tire Pressure Warning System section in the NA owner's manual, it shows the location of the receivers. But in my owner's manual, it only mentions these receiver locations for vehicles equipped with the TPMS that shows the display and not for those who do not. I hope the way I explained it is clear.

Sasnuke

Perfectly clear!
It's so strange they went through all that trouble to omit the feature when so many vehicles have it, even other vehicles in the lineup where you are have it. Just puzzling.