Imagine an automotive safety system that works, but not quite well enough. That is the case for 100,000 Mazda6 tire pressure monitor systems.
Who would have imagined a safety system that fails but doesn’t realize it? That is the case with 100,000 tire pressure monitoring systems used in 2014 to 2015 Mazda6’s.
According to thecarconnection.com, the 100,000 vehicles involved were built from Oct. 25, 2012 to Oct. 10, 2014. The problem lies in the tire pressure monitoring programming.
If one tire loses pressure suddenly, the tire pressure monitoring system will work correctly. In this situation, the software in the monitoring system relies, in the background, on a matrix of numbers that establish what the system sees as “normal.” Apparently somewhat time-based, the system will correctly report a tire that loses pressure catastrophically over a period of time. In this situation, the tire-monitoring system will tell you one tire or another has failed.
If, on the other hand, there is no quick or catastrophic failure in a tire, but, the failure is over a longer term with the tires losing their air charge at a equal rate so that all four of the tires are deflating at the same time and rate, the tire pressure monitoring system fails to see a failure and reports nothing is amiss.
In this system, the time threshold is not crossed. Instead, the air losses in all four tires remain in line with the matrix figures and continue to indicate there is no problem. However, there really is a problem uses certain benchmarks to determine whether the difference between the benchmark and the real-time report sent to the Mazda6’s ECU (electronic control unit) works as expected.
If the tires deflate at the same rate the system “thinks” everything is fine, but, this situation will actually leave you in danger of tires failing due to underinflation.
Mazda will begin mailing recall notices to the drivers affected by this issue. When owners receive the recall letters, the can go to their dealers for a free reprogramming to eliminate the issue.
Marc Stern has spent more than 40 years in and around cars. His work has included answering motorist questions, motor vehicle reviews and evaluation and writing dealers, consumer and industry news pieces. In addition, Mr. Stern has contributed to well-known automotive publications including Popular Mechanics, Mechanix Illustrated, AutoWeek and Old Cars Weekly, among others.