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What is TPMS?  How does it work? Why do I need TPMS?  The pros at Hilltop Tire Service of Des Moines know pretty much everything there is to know about TPMS and we’re here to help you benefit from this important safety system.  We will answer all these questions and more in this blog.

What Does TPMS Mean?   

TPMS stands for Tire Pressure Monitoring System, a safety system that alerts the driver if one or more tires is underinflated.

What is a TPMS Sensor? 

A TPMS Sensor is a small electronic device mounted on each wheel that is constantly monitoring the air pressure in each tire and sends a report back to the vehicle’s computer system if one or more tires is low on air.

How does the Tire Pressure Monitoring System work?  

Nowadays, there are two different types of TPMS Systems available, Direct and Indirect. The end result is basically the same, but they work completely different.

          Direct TPMS – This is the most common system. Direct TPMS uses sensors that are mounted on each wheel, inside the tire, that is constantly monitoring the air pressure and sends readings back to the main computer system. If the tire pressure falls below 25% from the vehicle recommendation, the sensor sends a message to the computer system and the low-pressure warning light comes on. The direct TPMS System is made up of 5 main parts: 4 air pressure sensors for each tire and the indicator in the vehicle’s main computer system. So, when it's time for vehicle maintenance or tire repairs, a direct TPMS system will be more expensive to replace.

          Indirect TPMS – Indirect TPMS, on the other hand, doesn’t use any extra parts.  This system works with the Anti-Lock Braking System (ABS).  The ABS monitors wheel speed, so if the tire pressure drops in one tire, it will roll at a different wheel speed compared to the other tires.  When the ABS computer notices this, it turns on the low tire pressure light.  Therefore, because it uses the ABS System to monitor tire pressure, no costly tire pressure sensors are needed and no additional costs are paid to replace this system.

How do I reset my TMPS Sensor?

In most cases, you can reset or turn off the TPMS Light by filling the tire with air to properly inflate the tire.  If all the tires are at the recommended level of air pressure and the TPMS light is still illuminated or is flashing, bring your vehicle to the nearest Hilltop Tire Service for further inspection, you may have a bad or damaged sensor.

Sometimes you may notice the TPMS light come on in the morning and turn off later in the day.  This is caused by temperature fluctuation.  Typically tires lose a pound of air for every 10-degree drop in temperature, so this is very common in the spring and fall when temperatures rise and fall.  You may want to consider filling your tires with Nitrogen to help with this. Read: Nitrogen Vs. Air in Tires.

Benefits – Why do I need TPMS?  

There are many benefits of having TPMS.  The Tire Pressure Monitoring System will alert you when the air pressure in your tires is low or going flat.  By maintaining proper air pressure in your tires, TPMS will increase your safety on the road.  With properly inflated tires you will improve vehicle handling and fuel economy and reduce braking distance and tire wear.  Driving on under inflated tires is like driving through sand, your vehicle has to work harder, which can lead to part failure and expensive repairs down the road.

Don’t Ignore the TPMS Light

Whether you need the tire pressure checked or TPMS repair, we’re here to help with all your automotive repair needs.  With state-of-the-art tire equipment and highly trained TPMS technicians, the pros at Hilltop Tire Service will have you back on the road in no time! Stop by any of our Des Moines locations anytime or schedule a service appointment online.