Early in 2007, I purchased a set of snow tires mounted on wheels with no air pressure sensors. I expected the dash warning light to go on, but it didn't.

Every fall since then I swapped the original tires with the snows and the light never came on. This year the light did come on.

Any explanation for this odd behavior?

EdP

 

If you put the summer tire in the garage when using the winter tire, TPMS sensor in the summer tire may be reachable from the on board computer. This may be the reason the TPMS indicator doesn't turn on.

I had the same experience. However if I drive more than 25 miles the TPMS indicator does turn on.

 

Interesting, but in my case, the summer tires are in a detached garage about 85 feet from the garage where I park the RX in the winter.

 

Do a test by deflating one summer tire?

 

Not sure what that is supposed to test.

Turns out that one of the summer tires is not only low, but flat.