TPMS / tire valve stem leaked air from tire. This is the second TPMS occurrence within last 2 months (from 2 different sensors). Service shop said that it was corroded.

- Huntington Woods, MI, USA

While driving at 70mph on US23 in Michigan, TPMS low pressure telltale illuminated. Within 30 secs, vehicle began to pull hard to the left. Pulled off the side of this 4 lane 70mph highway in the rain to investigate. Left front tire completely flat. Nut holding the TPMS sensor to the rim was missing & had corroded, allowing the TPMS sensor to fall inside tire cavity, resulting in rapid air loss. Threads of TPMS sensor exhibited corrosion. Drove vehicle to GMC dealership in Milan mi which confirmed the TPMS sensor nut failure due to corrosion. Tire destroyed, rim edge chewed up. Contacted Mazda usa and they would not offer any consideration, stating that the 3 year warranty had expired 1 month prior, and that corrosion was not covered beyond 3 years. I stated that this isn't a cosmetic rust issue, that the corrosion resulted in a safety concern for me and my family, but Mazda would not offer any resolution. The vehicle has been driven during 3 mild Ohio winters; there is not any signs of corrosion anywhere else on the vehicle; I drive the car thru automatic car washes every 3 weeks or so in the winter just to wash off any road salt. No other component on the vehicle is exhibiting corrosion. Had vehicle on lift to inspect the underbody. It does not seem technically sound that a vehicle component specifically mandate by NHTSA to prevent tires from being ran low in inflation pressure on a vehicle should instead cause my tire to rapidly lose all air pressure. This is a safety issue. I bought this vehicle new and know its service life. This TPMS sensor was in use for only 37 months. A 3 cent nut put my family at significant safety risk.

- Findlay, OH, USA

Valve stem broke off while low filling tire with air. Each time the tire looked a little low and when air nozzle was used it broke off and flew forcefully and all the air came suddenly rushing out. The computer low tire light was on the first time this happened, that is why I checked the pressure. I had to call service both times and had them changed tire and replace valve stem with non-computerized kind. They did not find any reasons that the tires had gone low other than the valve stem may have been already leaking. I then went to dealer to get new parts, which were still under warranty, and they said it was from misuse and wouldn't do anything about it. They were very rude. Said it was from hitting curb. It was not. The valve stem is well protected inside the rim. This has happened twice within the last six months. Both failures were nearly identical. I did not report the first time, but after checking around I found out this has happened to others and tire repairmen said they have had to change out several. Had I not seen that the tire was a little low and checked it in my garage this could have been much more devastating. I'm almost afraid to drive in case one of these would break on the road and kill me. The failures happened in December 2010 and April 2011. The vehicle I'm driving is a 2009.

- Norfolk, NE, USA