If you have a tire with 26 PSI or lower and you drive the car faster than 15 mph, your TPMS light should have illuminated to warn you of a low pressure condition. If your tire just goes flat in a parking lot without the car moving, your light will not come on. I have verified this with my own car. I aired one of the tires down to 20 PSI and started the engine. Did the TPMS light come on? Nope. But as soon as I drove down the street faster than about 15 mph, it turned on.
If, for some reason, your TPMS system is not alerting you to an obviously low tire when the car is moving at speed, then you've got a TPMS problem. But I can't tell if that's what you are saying.
You have a tire that's obviously leaking air somewhere...and it needs to be physically examined for signs of damage or possible puncture. You can do this easily yourself, or take the car to any reputable tire shop.
Air it back up and then check the pressure every hour or so. If the pressure is dropping that quickly, consider removing the wheel from the car (it's not that hard) and checking the tire for signs of a nail or something stuck in the tread. If you suspect the valve is leaking, spray some soapy water around the valve stem (with the cap off) and see if you see air bubbles. This should be an easy fix for any tire shop...unless you have a nail or damage near the shoulder of the tread. But we'll deal with that after you check out the tire.
Last edited by Top_Fuel; 09-02-2019 at 07:38 PM.
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View my fuel log 2015 Mirage ES 1.2 manual: 52.2 mpg (US) ... 22.2 km/L ... 4.5 L/100 km ... 62.6 mpg (Imp)