Does anyone know how accurate the readings from the TPMS is? I live in Denver and have been told by a Chevrolet dealer mechanic that it will always read about 4 psig lower than an accurate tire gauge because of the altitude. I assume that is because the TPMS sensors are calibrated for sea level and read absolute pressure and the computer deducts 14.7 psi to get a psig reading.

 

I had 2009 Suburban tires rotated and aligned yesterday at the dealer. After driving 50 miles, tire service light came on. I called dealer and he said the sensor needs replaced. Make appointment, cost about $100 for parts and labor. I live 60 miles from dealership and this is an added pain; this is the second time this has happened with this vehicle and same dealership in the 3 years I've owned it.

I'd like to know how to figure out if they just didn't reset the sensor on , as the threads mentions, or if it really does need replaced. Only one tire shows it has no sensor.

It was fine before I went in. Shouldn't the light have come on before 50 miles too?

 

Welcome to the forum.

$100 seems a bit high to replace one sensor. I bought four on ebay for about $150 and had them installed for about $80 at the dealer. The batteries are good for about 8-10 years. Strange that one would go bad following a tire rotation tho.