the tire pressure monitoring system warning light came on today on my way to work this morning i topped the tires off to the recommended psi (50) on the tires and the light went off. on my way home the light came back on. wondering what could be the issue?

 

50 PSI?!?!

The normal PSI on the OEM tires, and most tires you would replace them with, is 32-34 PSI.

The light comes on from over inflation as well as under inflation. It will flash if there is a system error.

 

They are definitely going over 50 psi once you warm them up, and just because it says maximum pressure 50 does not mean that is what should go in there. I generally air my tires up as cold as they get and shoot for 34-36 psi similar to what riwwp suggested.

 

That 50 psi is not the recommended pressure. It's the absolute maximum pressure the tire can stand, to be observed when mounting the tire and putting in extra air to seat the bead.

Ken

 

yeah i bled the tires back down to 35psi right after posting this, and it fixed the problem. Thanks guys for your help!

 

There should be a sticker in your driver side door jamb with the recommended tire pressure specified by Mazda.

 

As well as in the owners manual

 

WTF? What gave you the idea to pump in 50psi?

At least you probably gained 0.5 mpg from the lowered rolling resistance

 

He said he read the maximum pressure on the sidewall of the tire.
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The tires are extra load. The load carrying capacity is higher than some cars. To reach the maximum load carrying capacity, you need to use the maximum tire pressure. Although it's almost never needed outside of truck tires.

If you look at the sidewall for the rated load in LBS at the maximum pressure, you will see that your whole car can be supported by probably the weight of 2 tires.

Not just a one time thing either, like jacking up one side of the car. The load capacity in actual pounds is designed for using the tire at speed and under heat soak.

It would do no harm to run that specific tire at maximum pressure. Its not necessary though. It will create a rough ride.

 

+1 on that ^

 

Probably one of the most common car ownership mistakes is thinking the maximum pressure on the side of the tire is the recommended tire pressure for driving. An unintended consequence of that poorly written and designed stamp.

 

I cant count how many times people have come into my shop with 50,60,70+ psi in the tires and when I ask why, the answer is: "I pushed the button on the air pump at the gas station. When it stopped, I moved onto the next tire and pushed the button again."

 

You're correct. There is no harm to run near max rated pressures. Hell, ask any hypermileager what pressure they run and all of them will say damn near max.

Though it does get a much rougher ride compared to recommended pressure. It will be more prone to understeer also.