Last Weeks Car Talk Puzzler..Interesting.

On Car Talk yesterday they revealed the answer to their puzzler question.
Basically they said that ABS speed sensors can be used to detect low tire pressure because a wheel with a low tire would consistently spin faster.

If 2, 3, or 4 tires are spinning faster, you could reasonably assume:

-You would notice it without needing an alert
-You aired down and you would know that.

It had me wondering if the current TPMS sensor set-up is a "scam," just something extra to make money on.

It would be great if they could delete the current TPMS system by simply having the computer recognize data it is already collecting. Save money, time, complexity, hassle.




http://www.cartalk.com/content/snap-scanner-scenario-0?question

 

I'm guessing the TPMS sensor is more sensitive than the ABS sensors. The TPMS sensor will go off when you're only down a couple PSI, I'd guess the ABS sensor wouldn't start noticing a difference in wheel speed until you get low enough to actually make a significant difference in the outter diameter of the tire. Just my guess... Personally I think the TPMS is a dummy-light system and the only useful sensor is the spare (which they eliminated in 2009 or 2010).

 

The issue I see with programming the EBCM to take over TPMS duties is the now mandated VSC. How could you program the EBCM to know the difference between a low tire, a tire locking up and a low tire.

I see the EBCM having trouble sorting those 3 out. You'd have to have one hell of a programmer.