One step forward, two steps back: Frustration with the tire pressure monitoring system ruling lies with its uncertainty. When will we catch up with an ever-changing learning curve?

Aug. 1, 2005

On our last visit to Camp TPMS earlier this year, we learned that starting in September, 50% of the new vehicles manufactured for operation in the United States would be required to have a tire pressure monitoring system (TPMS). That number was to increase to 90% in September of 2006 and finally 100% by September of 2007.

Since then, the date for this year has moved back to October and the percentage of compliant vehicles has dropped to 20%. Only 70% will need to comply by the September 2006 date, but the 100% deadline remains the same at Sept. 1, 2007.

This section of the Transportation Recall Enhancement, Accountability and Documentation (TREAD) Act definitely can be considered an exercise that takes one step forward and two steps back.

But it doesn't stop there. The time period for the TPMS to detect low tire pressure has actually been increased to 20 minutes from 10 minutes. And despite objections from nearly every segment of the tire industry, the underinflation threshold to alert the driver has been left at 25%. But a provision for detecting a malfunctioning TPMS has been added (more on that later). There it is again, one step forward, two steps back.

It's reached the point where this version of the final TPMS ruling is being challenged in court, again. The old indirect system was successfully challenged in the past, but the premise was based on the assumption that consumers would be forced to pay the upgrade for anti-lock brakes. The fact that current indirect systems cannot detect four tires that are equally underinflated had very little to do with the decision. It was all about the rights of the consumer.

So once again, Public Citizen is leading the charge. But in a remarkable twist of events, Bridgestone Firestone North American Tire LLC, Cooper Tire & Rubber Co., Goodyear Tire & Rubber Co., Pirelli Tire LLC and the Tire Industry Association (TIA) have joined the lawsuit. All of the parties believe that the National Highway Traffic Safety Administration (NHTSA) has not fulfilled its responsibility to establish TPMS guidelines that protect American motorists from the dangers of underinflated tires.

The 25% under-inflation threshold is most likely at the epicenter of the debate. There are, based on my research, too many examples where a tire that is run 25% below its recommended operating pressure - thereby reducing its load-carrying capacity -- cannot support the weight of the vehicle. (Each vehicle's Gross Axle Weight Rating, or GAWR, is determined by the vehicle manufacturer.) Under these circumstances, the driver of a vehicle with an underinflated tire will not be immediately warned when a tire cannot support the weight of the vehicle.


TIA and others in the industry support a higher underinflation threshold with a built-in safety factor so these instances won't occur; NHTSA insists that the 25% threshold is sufficient.

On the other hand, the latest TPMS ruling definitely took a step forward with the Malfunction Indicator Lamp (MIL). This will notify the driver when the TPMS is not operating correctly.

According to NHTSA, if the MIL is a dedicated telltale on the instrument panel, it must contain the letters "TPMS." So when a driver sees the tire symbol it means the TPMS is detecting a low tire and when the driver sees the letters "TPMS" there is a malfunction. It sounds simple enough.

But the alternative to the dedicated telltale is a 60 to 90-second period at start-up where the low tire pressure telltale flashes, after which it will remain illuminated. So the driver has to know that the flashing low pressure telltale that stays illuminated means the TPMS isn't working and the telltale that doesn't flash but stays illuminated is the sign of an underinflated tire. Since every new car salesman will explain this to all of their customers (who certainly will remember), I'm sure there won't be any confusion when the dashboard light starts flashing or stays illuminated.

But this step backward for the consumer could be considered a step forward for the tire industry. One of the biggest concerns for retail tire dealers is an inoperable TPMS when the vehicle drives in the bay. A device is now available that enables technicians to determine if the sensors are transmitting before beginning work on the vehicle.

But the MIL telltale on the dashboard, either flashing or dedicated, will allow every dealer to immediately notify a customer of an inoperable system.

While on the subject of inoperable, the latest ruling addresses the subject of intentionally disabling a TPMS or MIL. Under 49 U.S.C. 30122(b), "A manufacturer, distributor, dealer, or motor vehicle repair business may not knowingly make inoperative any part of a device or element of design installed on or in a motor vehicle or motor vehicle equipment in compliance with the applicable motor vehicle safety standard prescribed under this chapter unless the manufacturer, distributor, dealer, or repair business reasonably believes the vehicle or equipment will not be used (except for testing or a similar purpose during maintenance or repair) when the device or element is inoperative."

This creates a serious issue for dealers who install custom tire and wheel assemblies that cannot accommodate the valve stem sensors. But NHTSA has determined that when aftermarket assemblies prevent the TPMS from functioning properly, "such equipment arguably has not damaged the TPMS itself, but instead has hindered its low tire pressure detection capability.... Once the TPMS MIL illuminates, the consumer would be warned that the equipment has caused a TPMS malfunction, and the consumer could substitute other equipment that would permit the TPMS to resume normal functioning."


Government intervention

On a positive note, the amount of available resources for maintaining, repairing and servicing tire pressure monitoring systems continues to increase. From tools and equipment to training, dealers can be more prepared each year that we get closer to 2007. As frustrated as I get with the apparent one step forward, two steps back approach, I have to constantly tell myself that we're dealing with "new" technology so it will change on an annual basis with each new model year. And as a NHTSA engineer reminded me, the final ruling represents a minimum standard and manufacturers can, and probably will, exceed it for competitive purposes.

I also can't forget that throughout the rulemaking process, NHTSA engineers have carefully evaluated the comments from manufacturers, suppliers, industry organizations and other interested parties. They researched the claims, checked the facts and ultimately presented what they believe was the best solution to the problem. At that particular moment in time, safety is the top, and perhaps only, priority.

The second step in the process involves government officials from different agencies who each look at it from their own perspective. This is often the stage where the budget-minded people show up with boxes of data that show the "super-safe" program will cost the auto manufacturers millions of dollars on top of the millions of dollars they've already spent to comply with the existing rule. They'll have indisputable proof that the "safer-than-it-was" approach will accomplish most of the goals at a lower cost to the vehicle manufacturer.

Forcing higher costs on a struggling industry is difficult to justify from a political perspective, especially when dealing with new technology.

Maybe that's the most important thing we need to remember: TPMS technology is still new technology. Everyone from the engineers in Detroit or Japan to the tire technician in Amarillo, Texas, is on a fairly steep learning curve. A lot of lessons are going to be learned over the next few years, so it's logical to assume that the systems of today will be very different from the systems of tomorrow.

In five years, valve stem sensors could be ancient technology. The next generation of tire pressure monitoring systems could use the ABS or a computer chip built into the tire to instantly monitor the inflation pressure. Recalibration could be a universal procedure where all you have to do is press a button on the dashboard or, even better yet, it happens automatically. We are in the infancy stages of tire pressure monitoring, so it should only get better from here.

But "here" is exactly where we are stuck and we have to be able to service vehicles with the current technology in place. As more resources become available, dealers who want to remain competitive until 2010 and beyond must be constantly evaluating tools and training programs to ensure that technicians are prepared for whatever rolls in the door. Because once 2008 model-year vehicles begin showing up for their first set of replacement tires, companies that still need to learn the ins and outs of TPMS technology might be taking one step forward and two steps back.

This article is part of a regular series written exclusively for Modern Tire Dealer by Kevin Rohlwing, senior vice president of education and technical services for the Tire Industry Association.

About the Author

Bob Ulrich

Bob Ulrich was named Modern Tire Dealer editor in August 2000 and retired in January 2020. He joined the magazine in 1985 as assistant editor, and had been responsible for gathering statistical information for MTD's "Facts Issue" since 1993. He won numerous awards for editorial and feature writing, including five gold medals from the International Automotive Media Association. Bob earned a B.A. in English literature from Ohio Northern University and has a law degree from the University of Akron.