What does TPMS Mean on a Car and How it Works

The acronym “TPMS” stands for “Tire Pressure Management System” in a car. It is one of the newer pieces of technology in modern vehicles. The purpose of the TPMS is to let you know if one of your tires is underinflated, overinflated or losing air. It is important that you keep the air pressure in your tires within a certain range. You can find the exact range in the owner’s manual of your vehicle.

The TPMS contains a series of sensors which transmit all the tire pressure information to the engine control unit of the vehicle. The engine control unit is the central computer of the vehicle which communicates with all the sensors in order to monitor the various systems and components. When the engine control unit finds out that one of the tires has low or high pressure, it activates the TPMS warning light on the dashboard.

As you know, having low tire pressure in any of your tires can make driving conditions unsafe for your vehicle. Your driving experience won’t feel as smooth, and there will be a lot of friction created between the low-pressure tire and the road. Like in the engine, friction generates a lot of heat between the two elements rubbing closely together. In this case, the tires are exposed to more heat as they move on the road. All that heat will cause the tire treads to wear down and flatten a lot faster.

If you have overinflated tires, then your driving experience won’t be that great either. Your tires will be no different than the solid wheels of a covered wagon. The ride will feel rough and shaky the entire time. When this happens, the TPMS is prompted to notify you with the warning light as well.

The Two Types of TPMS

Car manufacturers use one of the two different TPMS systems in their vehicles. They are as follows:

Direct TPMS – A Direct TPMS is where each wheel of your vehicle has a sensor mounted onto it. The sensor measures the air pressure directly, hence the name “Direct TPMS.” If the air pressure falls below 25% of the recommended PSI level, then a signal is sent from the sensor to the engine control unit. This is what prompts the TMPS light on the dashboard.

Indirect TPMS – An Indirect TPMS is integrated into the Antilock Braking System of your vehicle. It basically collaborates with the wheel speed sensors of your Antilock Braking System to determine whether the pressure is low. If low pressure is in one of the tires, the wheel speed changes. The difference in the wheel speed compared to the other wheels will be noticed by the engine control unit. This causes the TMPS light to come on.

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Tires are the most vulnerable parts of your vehicle. Not only are they flimsy, but they’re constantly in contact with the rough solid ground below. If your tires are losing air, they run the risk of going flat. The TPMS allows you to recognize this is happening so that you can do something about it before one of your tires actually does go flat. Then you can prevent yourself from getting stranded on the side of the road and ruining your day.

As mentioned above, low tire pressure wears down the tire treads significantly. If the tire treads flatten too much, your vehicle won’t move as smoothly. Then your engine is forced to generate more power in order to keep the vehicle moving. This, in turn, weakens your fuel economy and makes you pay more money on gas each month. So, if you can figure out your tires have low pressure ahead of time, then you can fill them up with air and keep your fuel economy and tires in good condition.

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