Bryan Auto Repair


Why is my tire light on?

Why is my Tire light on?

Well that is a great question. Today’s cars have tire monitoring systems (known as TPMS Tire Pressure Monitoring System) that help you know when a tire is getting low on air. This stems from safety issues in the past that caused a great deal of damage and even death. The light comes on to let you know that one or more tires are below/above a safe pressure level; this allows you to make adjustments as needed to keep you and your car in safe working order. In addition to safety, the TPMS also has another benefit: it saves on fuel and helps tires last longer.

How Does it Work?

Well there are 2 systems that monitor tire pressure. Indirect TPMS and Direct TPMS. Both do a remarkable job, but work completely different ways. Indirect systems rely on the ABS wheel speed sensors to monitor tire rotation. A low tire or an over-inflated tire will have a different circumference than the properly inflated tires. This causes a slight difference in tire RPM and turns on the light. The advantages of indirect is it cost less to maintain and build. Since there is no battery or sensor in the wheel itself, there is very little to go wrong. The disadvantage of this system is it will not monitor the spare tire and cannot give real time pressure of the tire.

Direct works by installing a pressure sensor in the tire that reads the actual tire pressure and sends a wireless signal to the monitor. The monitor then makes sure the pressure meets the parameters to run properly. The big advantage you have here is seeing the actual pressure and monitoring the spare. No one likes having a flat, but imagine having a flat and finding out the spare is flat too…!!?? That is a no win, in so many ways. Many direct systems also monitor tire temperature, which is the #1 cause of blowouts. The down side of this more complex system is there is more maintenance in that any of the sensors can fail. The battery for these sensors are rated 8-10 years, but that is not always the case. The sensors can also be damaged during tire replacement and the programming can sometimes be problematic.

All that being said, TPMS is here to stay and in the overall scheme of safety that is a good thing!

If you have a light that won’t turn off, let our team check it out for you! Click HERE to make your appointment with us!

B&B Automotive Services is committed to ensuring effective communication and digital accessibility to all users. We are continually improving the user experience for everyone, and apply the relevant accessibility standards to achieve these goals. We welcome your feedback. Please call B&B Automotive Services (979) 775-3413 if you have any issues in accessing any area of our website.