Can anyone provide a general explanation of how the low tire pressure light works? Where is the sensor or sensors located and what exactly triggers them?
Thank you

R/F signals. Sensor in each tire, and a receiver in the vehicle set to certain parameters.

On Mine, I have aired up all the tires to the Correct Air Pressure, but still get the "Check Tire Pressure", doesn't seem to want to Reset? How do I correct This?

Probably a dead battery in one of the wheel sensors. Need to take it to the dealer and he should be able to diagnose which one it is for you. For a charge of course.

:D Well since I'm a Heavy Duty Truck Mechanic by Trade, and Have LOTs of Tools, I was Hoping maybe You could tell me the Procedure for Doing that, why go to a Dealer when I could do the work myself...

Can you safely dismount and remount tires? Tires need to be removed from the wheels to get at the sensors.

Not necessarily. The id codes can be read from outside the tire with a code reader. If you stop by a tire shop, someone there should have one handy and see which one is not responding.
Be sure the spare is not the culprit.

Also, some GMs can reset the tire light through the radio; depends on the radio design.

:confused:
Hmmmm, never heard that before, so HOW do you do that? I don't have an "Idiot-light", mine is on the Sensor Array Read-outs on the Left side of the Dashboard.

From what I can find, I don't think your car can do it through the radio. Have you tried turning the key on, then stepping & releasing the gas pedal a few times?

The method of turning the key on and mashing the gas several times is for the oil life index (on some makes and models). Nothing to do with the Tire Pressure Monitor (TPM) system.

Mounted into each wheel is a combination tire fill port and tire pressure monitor. The monitor is a tiny silicon pressure sensor that responds to, you guessed it, tire pressure. The sensor also uses a tiny battery that powers a small transmitter. Each sensor has a unique ID that tells the on-board computer the tire pressue detected and, once "learned" with a scan tool, the position on the vehicle.
It is necessary to enable the TPM module to learn. Using the Driver's Information Center (DIC):
Set all tire pressures to manufacturer's specifications.
Turn ON the ignition, with the engine off.
Press the GAGE INFO button until TIRE PRESSURE is displayed.
Press and hold the RESET button until TIRE PRESSURE RESET is displayed.
Release the RESET button, TIRE PRESSURE NORMAL is displayed.
Use the scan tool in order to clear the TPM DTC, if any are stored, and there probably is.
If all the sensors are functional, the light should go out. If not, you'll need a proper scan tool to determine which TPM sensor isn't. If replacement is necessary, you'll need the proper scan tool to "learn" the location on the vehicle of all four (they learn in sequence, starting with the RF, then the RR, then LR and then LF).
These sensors are subject to heat, vibration, moisture, etc. and can simply run out of battery and no longer capable of responding. Replacement is the only option.

I could've sworn I read in one car's manual that would also reset the tire light, but I might have been mistaken. I also have a customer with a '97 Century that no matter how many times you do the gas pedal trick, the stupid oil light refuses to reset itself.

They can never just keep it simple, can they? Lol :)

How can the same prodedure reset work both systems? Every time you reset the tires, the oil life index would reset, and visa-versa.

First, make certain the floor mats aren't bunched up under the accelerator pedal before you begin. Keep in mind, it's not to be done too fast or the system won't "see" the change from closed to wide open throttle.

To reset the "CHANGE OIL SOON" indicator:

Turn the ignition to the "ON" or "RUN" position without starting the engine.
Fully press and release the accelerator pedal three times within five seconds.
If the "CHANGE OIL SOON" indicator flashes two times, the system is reset.
If the "CHANGE OIL SOON" indicator comes on and stays on for five seconds, try to reset the system again.

If the vehicle is equipped with a driver information display in the instrument panel cluster, the system may be reset by pressing the "DIC RESET" button for five seconds while "OIL LIFE" is displayed.

We tried everything. It's just that one particular car that refuses to reset. I can try a dozen times; fast, slow, removing the floormat from the car entirely. The light just won't flash to indicate it's been reset.

On an 01 buick the sensors are indirct so the sensors are ot on the inside of the tires they are built in with the abs sensor and you don't have to worry about them when breaking down the tires. There is supposed to bea reset button. But I don't honestly know where if someone does please let me know. Direct tpms is mainly on o7 and newer models, now there are some on years as early as 04 but all vehcle made for 08 and newer have to have it except for dually trucks

THANKS for the INFO!!
I got the Problem FIXED at My Local Tire Shop, they checked and Corrected all the Tire Pressures, and did a "RESET" in the Read-Out Array on the Dash...Problem solved:)

There's a yellow button on passenger side of car in the fuse box by glove compartment. Have to reset this button each time put air in tires or rotate tires.

There is a fuse panel on passenger side open the panel turn on the key press and hold the reset button blinks turn key to off position . Do not start the car when you turn the key on