How many pounds below the pressure setting I choose for my tires does the pressure alarm indicate low pressure? Is it preset for factory recommendations? If I were to choose 40 pounds, would it indicate low pressure at, let’s say 32, instead of 26? Is it a percentage below current pressures?
Welcome. I assume you have a Prime since this is in the Prime forum. (The same would be true for any Gen 4, I think.) It would be really really helpful if you put your car in your profile info. Location also often helps. Anyway, I don't know the threshold either, but it's based on the pressure you have when you initialize it in the car's settings.
Every Toyota I've had has been ~5 lb threshold. I sometimes pump them up a few lb higher than I want then reset the TPMS before lowering them down again. That way I wind up with a 2-3 lb threshold.
Yeah, I have never checked the exact threshold on mine. But it should be easy to check. Just let the air escape from the tire and check the psi and drive a few miles to see if the TPMS warning light comes on. I would check it for you if I still had the car, but I no longer own a car, so I must wait for someone to check this.