the tmps light on my truck keeps coming on usually after it got cold . . . tire never looks low, and i can drive months with light on, but not lose anymore air from the tire . . it takes constant servicing to keep the tires over 35 lbs to turn the light off. why is this? is the sensor bad? or the computer on the truck malfunctioning?
My car has 40000 miles.
My car has an automatic transmission.
Hello - most likely this is not a malfunction of the TPMS sensors or any other vehicle system. This is caused by the drops in temperature - which decreases the pressure in the tires; just as tire pressures increase while driving. Tire pressure can decrease enough to trigger the TPMS sensors during a change in season, or after a cold front rolls through. This is by design, in order to prevent excessive tire wear at the edges of the tire due to underinflation. The only solution, and the desired solution, is to add air to tires as temperatures drop, and let air out in the spring when temperatures rise. If tire pressures are all at the specified temperature, have the TPMS system examined by a reputable tire dealer in your area. The tires must be removed for this check. Unfortunately, this is not a service YourMechanic can offer. Thanks for thinking of us!
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