Tire Pressure Monitoring System problems of the 2007 Jeep Grand Cherokee

While checking the tire pressure on a customer's vehicle, the tire valve on the tpms sensor broke.

The automotive oil change association (aoca) represents the fast lube industry, with more than 3,500 locations in north America, servicing more tires than any other organization. Over the past several months members reported an increasing number of problems with tire pressure monitoring systems (tpms) and they are getting worse. Conventional tpmss measure tire pressure at the valve and use a radio frequency to transmit the data to an antenna on the side of the vehicle. The quality of these valve stems is so poor that car care professionals know - if they check the tire pressure, it is likely the valve will break and they will incur the cost to replace, about $110. 00 per unit. Specifically, the 2008 Jeep Grand Cherokee, and the 2008 Chevrolet equinox, have aluminum valves stems; these easily corrode, become brittle, and break at the touch. They also have a plastic cap. If this plastic cap is improperly seated, or replaced by an aftermarket cap containing brass, or brass thread inserts, it leads quickly to galvanic corrosion; the result- the cap fuses to the valve stem. Attempt to remove the cap, the stem breaks. The driving public is being trained to trust these monitors for accurate tire pressure. Properly inflated tires reduce the potential for life-threatening blowouts, enhance handling, improve fuel efficiency, and prolong tire life; lowering the cost of ownership. These systems are too fragile to continue using them in passenger vehicles without addressing the durability. As these systems age, failure will increase 100%. Tpms units are specd out by oems- manufactured by siemens vdo (acqd by continental ag in may 07). Aoca has made many inquiries to see if these units are intended to be recalled or redesignedthe resounding answer is no. If oems do not change the specs tpmss will continue to be poorly made. Aoca asks NHTSA recall these units to protect the consumer, and people maintaining the tires on vehicles.