The Tire Pressure Monitoring System (TPMS) is a crucial component in modern vehicles. It plays a significant role in improving fuel efficiency, extending tire life, and enhancing vehicle safety. The TPMS is represented by a light on the dashboard, typically shaped like a tire cross-section (resembling a horseshoe) with an exclamation point in the middle.
Table of Contents
What is a TPMS Sensor?
A TPMS sensor is a device installed in a vehicle’s tires. Its primary function is to monitor the air pressure and temperature of the tires. Low tire pressure can lead to uneven wear on the tires, increase the risk of blowouts and accidents, and decrease fuel efficiency. Therefore, maintaining the correct tire pressure is essential for the overall performance and safety of the vehicle.
How Does a TPMS Sensor Work?
TPMS sensors are typically installed inside the tire’s air valve stem. They can be either mechanical or electronic. These sensors measure the tire’s air pressure and temperature and wirelessly send this information to the vehicle’s onboard computer. If the pressure in one or more tires is too low, the computer will signal the driver via a warning light (icon) on the dashboard. When the driver inflates the tire, the sensor automatically recalibrates, and the warning light turns off.
Maintenance of TPMS Sensors
Maintaining and calibrating TPMS sensors is crucial for their proper functioning. The batteries on the sensors need to be replaced periodically to ensure that the system works correctly. Over time, TPMS sensors can become damaged or lose their accuracy and must be replaced. Also, if the tires or wheels are replaced or rotated, the sensors must be re-calibrated or replaced to work correctly.
Types of TPMS Sensors
There are two main types of TPMS sensors: direct and indirect.
| Sensor Type | Description |
|---|---|
| Direct TPMS sensors | Installed inside the tire and directly measure tire pressure. |
| Indirect TPMS sensors | Monitor the wheel speed and infer the tire pressure based on changes in the wheel’s rotation. |
Both types have their advantages and disadvantages, and the choice between them often depends on the vehicle’s specific requirements. Some vehicles come with a combination of both types of sensors, and some newer vehicles have TPMS sensors integrated into the tire pressure monitoring valves in newer vehicles.
Symptoms of a Faulty TPMS Sensor
A faulty TPMS sensor can manifest in several ways:
- Warning light on the dashboard
- Incorrect tire pressure reading
- Inaccurate or no tire pressure readings
- Warning light stays on even after inflating the tires
- Warning light icon turns on and off intermittently
- Dashboard shows TPMS system failure icon
If the warning light turns on and off intermittently, it could indicate a malfunctioning sensor. Other issues, such as a malfunctioning receiver or a problem with the vehicle’s onboard computer, can also cause these symptoms. If you suspect a problem with your TPMS, it’s recommended to have the system inspected by a professional.
Benefits of TPMS
The TPMS provides several benefits, including:
- Provides visual warning of low pressure while travelling
- Reduces risk of tire failure
- Helps to ensure optimal tire pressure
- Decreases tire wear from incorrect pressure levels
- Maintains vehicle handling
However, even with a TPMS, it’s still necessary to manually check the air pressure regularly.
TPMS Repairs and Maintenance
Ignoring the TPMS light can lead to serious issues down the line. If your TPMS isn’t working as it should, it’s important to seek professional help. Technicians can check your vehicle’s tire pressure, perform a systems test on your tire sensors, and diagnose any problems.
Summary
In conclusion, TPMS sensors play a vital role in monitoring the air pressure and temperature of the tires. A faulty TPMS sensor can lead to increased risk of a blowout or accident, decreased fuel efficiency, uneven tire wear, reduced handling and stability, and incorrect readings. Regular maintenance of TPMS sensors, including regularly checking tire pressure, calibrating and reprogramming sensors after tire replacement, cleaning and inspecting valve stems, and replacing batteries in sensors, is essential for the overall performance and safety of the vehicle.
Frequently asked questions
Where is the TPMS reset button?
- Under the steering wheel
- In the instrument cluster
- On the driver’s door panel
- In the infotainment system
- In the glove box
- On the center console
The exact location can vary by vehicle make and model. The button is usually labeled with “TPMS” or the low tire pressure symbol. If you can’t find it, refer to your vehicle’s owner’s manual.
To reset the TPMS, typically, you hold the reset button until the TPMS light blinks three times, then release it. Start the car and wait 20 minutes for the sensor to refresh.
How do you reset TPMS without reset button?
- Drive at a certain speed: Some vehicles automatically recalibrate the TPMS sensors after you drive at a certain speed (usually around 50 mph) for a certain distance (usually around 10 miles)
- Inflate and deflate the tires: Inflate each tire to its ideal PSI, then deflate the tires to zero. Then inflate again and drive for a couple of minutes at 15 mph to manually calibrate the sensors1.
- Use the ignition: Turn all accessories off. Turn the key to the “On” position with the engine off for 20 minutes and then drive the vehicle above 16 mph for at least 7 minutes.
Why is my TPMS light on but tires are fine?
- Faulty or Unprogrammed Tire Pressure Sensor:
The TPMS sensor can lose the programmed data or get damaged, causing the light to remain on. You may need to reset the TPMS system with a scanner or check the procedure for your specific car model. - Dead Battery in Sensor:
The batteries in the TPMS sensors can fail, causing a breakdown in communication and the light to come on. - Defective TPMS Receiver:
The receiver of the TPMS can fail, leading to a loss of pressure data from the tires. - Traction Loss:
If your car uses an indirect TPMS configuration, any loss of traction could cause the light to come on1. - Ambient Temperature Change:
Changes in temperature can cause the tires to contract or expand, triggering the TPMS light.
Is it safe to drive with TPMS light on?
Driving with the TPMS light on is generally unsafe as it indicates a potential issue with tire pressure, which can affect handling and increase the risk of a blowout.
However, if the tire pressure is confirmed to be fine and the TPMS light is on due to a faulty sensor, it may be safe to drive temporarily. But the faulty sensor should be replaced as soon as possible to ensure the TPMS system is working correctly.