How are TPMS thresholds set?

[desura]

Recently my TPMS went off. It was from one of my tires which is always a little low on pressure.

Now, the tires are high efficiency, so they're all 40 PSI. The low tire pressure was just at 30.

Is TPMS light going off about the tire being a certain deviation below the rest of the tires? Or is it at a set threshold? I'll be changing tires to winter soon so I don't want the light to be on all the time for them because they all will be lower PSI.

 

[HarryLui]

Year, make, model probably makes a difference and if your car is under warranty, call the dealer and ask.

 

[pcgeek11]

Most cars and trucks have a reset switch and procedure in the Owners Manual that sets the threshold once all the tires have been set to the level desired by the owner.

Short story look in the owners manual.