Some of you may already know that Tire Pressure Monitoring Systems (TMPS) were mandated by Congress in 2000 under the TREAD Act to warn drivers of underinflated tires. As a result, all vehicles manufactured since 2007 are equipped with some kind a TPMS system and many higher-end vehicles came equipped with TPMS as early as 1996.
In general, the tire industry has adapted to the service of sensors and most reputable shops will have no problem ensuring that they are reset following a tire installation. However, what consumers need to know is that every sensor is powered by a small, non-rechargeable battery that cannot be serviced or replaced. The estimated lifespan of these batteries differs by manufacturer, but the industry consensus is that at 5 -7 years or 70,000 miles, the sensors will begin to fail, illuminating the TPMS warning light on the dashboard of the vehicle. This light is more than a nuisance – beyond the very real safety hazard of driving with underinflated tires, in most states the illuminated TPMS light is an automatic inspection failure.
This is about to be a huge problem for millions of consumers on several fronts. First, the sensors are expensive, with each unit costing as much as $100 and most vehicles requiring five units (for the four main wheels and one spare). Worse, because the sensors are mounted inside the wheel, installation requires the dismounting, remounting and re-balancing of all five tires. If this is being done anyway, say in the course of an ordinary tire replacement, mounting the new sensors is inexpensive, averaging $10 additional per wheel. The problem arises when the consumer replaces the tires without replacing the still operating (but aging) sensor- let’s do the math for a 2007 Touring Sedan with 60,000 miles for which you purchase 40,000 mile warranty tires with about 6 months – year worth of sensor life left:
Tires & Sensors Purchased at the same time
| Cost of 4 Tire Installed | $700 |
| 5 Sensors | $500 |
| 5 Sensor Installs | $50 |
| 1 Mount + Balance for spare | $25 |
| Total | $1275 |
Tires & Sensors Purchased Separately
| Tires (Today) | Sensors (a year later) | ||
| Tires Installed | $700 | ||
| 5 Sensors | $500 | ||
| 5 Sensor Installs | $50 | ||
| 5 Tire Mount + Balance | $125 | ||
| Total | $700 | $675.00 | $1,375.00 |
By being proactive, the consumer saves themselves a trip to the tire store (or in our case an on-site appointment) as well as $100 on install
In some newer vehicles, manufacturers have added rechargeable units, extended the lifespan of the battery to 10+ years, or adopted so-called “indirect” systems that don’t use an in-tire sensor at all. However, if you own a car that is over 5 years old that is equipped with TPMS, a failure is in your future and you are better off biting the bullet and changing them out with your tires.
The internet is full of advice on this topic and one bit that we see frequently is the suggestion to buy sensors online and then have your local shop do the install. We don’t have any major qualms with the quality of the more reputable aftermarket parts (although we prefer to use OEM). However, many of the discount OE suppliers can offer low-cost stock specifically because they have aging batteries inside… so buyer beware.
TPMS increases driving safety, improves fuel economy and increases tire life by proactively alerting the driver to an underinflated tire. Replacing the unit before it has failed is money well spent.
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