Tire pressure sensors and cold weather

My 2010 Honda Civic has tire pressure monitoring sensors. Without fail, even if the tires have been recently inflated (last Wednesday) when the temperature falls to about 25 degrees, the indicator comes on. This happened with the tires I had previously and with the tires I had put on (with new sensors) in July. I even took the car back the next day once and had them check the pressure and they said it was the same in all four tires, but the indicator still came on. Without any action, when the temps warm up again the indicator goes off.

Anybody know what’s happening here? It’s really annoying and I’m thinking about having the sensors removed/disconnected because they’ve never actually done me any good.

Are these the original equipment sensors that came with the car? Does your Honda allow you to input settings to the onboard computer for the tires/sensors like the load, summer/winter, etc?

No, the current tire sensors are not original. Not sure about the prior ones. This did happen with the originals too, though. I don’t know about being able to change the input settings. I should probably ask a mechanic then?

Well, when air gets cold, its pressure does decrease. So I guess if you were inflating your tires to that they were just on the fine edge of having enough air, then a temperature change would be enough to set off the sensors. But I wouldn’t think that the effect would be that noticeable for a 25 degree change.

Still, you might just try inflating your tires an extra couple of PSI and see what happens.

Get a tire pressure gauge. When the light comes on, check all 4 tires. If the pressure is in spec you can ignore the light. But don’t ignore the light without checking the pressure first!

PV=nRT

The volume of air in the tires is constant, so when temperature drops, so does the pressure.

As I understand it, the sensors don’t indicate a change in pressure but differences in pressure between the four tires. Theoretically, the pressure should change in the tires at the same rate.

I do ignore the light but the light is annoying. I want the light to go off.

Increase the tire pressure by 10% in all four. My Nissan Sentra does that every cold snap.

Just happened on my wife’s 2012 Nissan Altima. I’d checked the tire pressures about 2 weeks before when it was around 65°F and it dropped into the 20s a couple of days ago. I thought that there was a tire going flat, but they all had the same PSI, which was only 4 PSI less than recommended. My other cars are much more forgiving about the pressure drop.

BTW: Just a friendly reminder to all to also check your spare tires about once every 6 months. You don’t want to find out that you actually have 2 flat tires at a bad time. I’ve seen spare tires down 40 PSI on new cars and even lower on family and friends older cars.

I have a Mini Cooper that does that too. This morning again, as a matter of fact.

There is a way to reset the warning which isn’t too difficult. That just resets the sensors to say that the tires are at the appropriate pressure, and turn off the light. Check the owner’s manual and see if you can find it. It took me a while to find how to do it, and I don’t know what I finally found it under.

Have you checked the spare tire? A lot of cars nowdays have full size spares and they also have the sensors on them.

There should be a sticker in either your glove box or on the door frame that gives the recommended tire pressure for your car. If you don’t have a tire pressure gauge, buy one. Then check your tire pressure and inflate your cold tires to spec. Sometimes the car has to drive a bit for the sensors to go off.

My daughter’s Honda Fit has this exact same problem. Her tires are at the proper pressure; she just ignores the warning until spring. Some “safety feature” :rolleyes:

Several above have suggested checking all ***four ***tires. On some vehicles the spare tire is often the offending member; may or may not be applicable for the OP.

#10: Since most car tires pressure is around 32 to 35, how can pressures be down 40? I’ve rread it over several times, and I don’t see what I’m missiong.

I assume he’s speaking in metric. 32 pounds per square inch is about 220 kilopascals.

ETA: Apparently he’s not, since he specified PSI.

Have the tires filled with Nitrogen. Tires filled with Nitrogen change pressure less due to temperature changes.

Tire pressure sensors are set to go off at 20% below recommended pressure. If the recommended pressure is 35PSI the light will trip at 28PSI.
Next is you probably have no idea of the accuracy of you tire gauge or of the one the shop has. I have a reference standard setup for my technicians to check their gauges against.
Most are within a lb or two but I have seen gauges be 8+ lbs off coughharborfreightcough
Also what pressure did the shop set the tires to? Where they set to what is recommended on the inflation placard or did they just put 32PSI in them because that is what they learned 20 years ago?
Finally tire pressures should be set cold meaning within one mile of starting out. The pressures listed on the placard are for cold tires.

I suspect you have a combo of an incorrect gauge, pressures set hot and pressures not set to specification.

Oh and the 40 PSI mentioned for the spare? Lots of space saver spares inflate to 65PSI or more. 40 would be almost flat for one of those tires.

While we are on the subject if you own a newer car many new cars no longer have spare tires, but just have a pump and a can of goop. If you haven’t looked where the spare should live you might want to check and see if your car has a spare.

Remember when we would actually check our own tire pressures? TPMS is an imperfect technology, IMHO. Some vehicles are location specific; it might say left front is low. But if your local mechanic rotated your tires, it gives wrong information. If you have a malfunctioning sensor, the light in your dash is on at all times, and for no reason.