Roughly two weeks ago my tire pressure light came on. I proceeded to the gas station to check the pressure. It was a bit low, I filled it and the light went off. This has been going on for two weeks now everyday we fill the tires and within hours the light comes back on. We took it to a mechanic to have it checked and low and behold he advised us that the stems/sensors are bad. On all 4 tires. This makes no one bit of sense to me. Any suggestions or any knowledge of this being a recurring issue with this year/make/model Mazda/3/2010?
I suggest that you obtain a second opinion, because you may simply have a slow leak from a nail or around the valve stem. I would investigate further before resorting to replacing all (4) sensors.
Hope this helps!
Do you live in a colder region where road salts are used? We have heard of sensor corrosion being an issue, especially in colder climates. Another issue is galvanic corrosion, which occurs if the sensor stem and the cap are made of different metals.
One other problem could be the sensor's batteries, although with the age of your vehicle this probably isn't the cause. Most estimates for sensor battery life are 6-7 years.
〉 Answered on Jan 17th, 2013 by Denise Koeth, Managing Editor at Tire Review Magazine