• Skip to primary navigation
  • Skip to main content
  • Skip to primary sidebar
  • Skip to footer
  • Subscribe
  • Advertise

Sensor Tips

Sensor Product News, Tips, and learning resources for the Design Engineering Professional.

  • Motion Sensing
  • Vision systems
    • Smart cameras
    • Vision software
    • Lighting
    • Optics
  • Pressure
  • Speed
  • Temperature
  • Suppliers
  • Video
    • EE Videos
    • Teardown Videos
  • EE Learning Center
    • Design Guides
    • Tech Toolboxes

The automotive Tire Pressure Monitoring System, Part 4: Issues

October 8, 2021 By Bill Schweber

Sensor-based monitoring systems for tire pressure can warn of potential problems, but there’s much more to the story than just a pressure-measurement system.

The TPMS adds a highly specific safety-related feature to cars. However, as with many presumably good ideas, the “devil is in the details”, and that’s especially true for the TPMS. There are many issues associated with the TPMS, among them:

  • The RF link is very low power to extend battery life. Due to the weak signal and the general automotive RF environment, it is subject to internal and external EMI-induced errors.
  • The very weak RF signal can be blocked if something metallic (such as lunch in an aluminum-foil wrapper) is put in the wrong place, which varies by car; for some cars, putting lunch under the driver’s seat can block and cause the loss of the signal.
  • The battery in the TPMS unit in the tire has a life of only 5-10 years depending on various factors and is not replaceable, so the entire module must be replaced. In reality, the units for all four tires should be replaced simultaneously, so we’re looking at several hundred dollars. The replacement must be the same type and frequency as the originals, of course.
  • If you have to replace a tire due to failure or routine wear, the same replacement scenario applies to end-of-battery. The TPMS module itself can also be damaged by hitting a curb or pothole.
  • Not surprisingly, the sensor and entire TPMS need to self-calibrate after module replacement, keeping things steady for a few hours to a few days. Going on the highway and heating up the tires – and thus increasing their pressure – too soon after replacement can corrupt the calibration process. The TMPS includes a temperature sensor in each module to incorporate a temperature reading into the algorithm, which computes pressure from the send variables.
  • Transient shifts in tire temperature such as occur when going from a heated garage to a cold outside can also cause false readings; again, the temperature reading must be used.

To provide additional insight to the driver, most cars allow the driver to invoke a console display that shows each tire’s pressure (Figure 1). This is more information than just the low-pressure indicator.

Fig 1: Many vehicles have a “hidden” function which the driver can invoke and which sets the console to display the actual tire-pressure value for each tire. (Image: Car and Driver)

While this is useful, most drivers don’t understand that a displayed value can easily “chatter” by ±1 PSI (or the least significant digit, if readings are in bar units). To minimize this occurrence, the TPMS software adds some hysteresis to the displayed reading to stabilize it and minimize unneeded confusion or worry. Also, the observed pressure will legitimately increase by several PSI as rolling friction heats the tire; this, too, can cause confusion.

Finally, as with most data systems, it is possible to lose synchronization or ID for an individual TPMS unit or need to reset or recalibrate the sensor. Obviously, this must be done via a wireless link. Mechanics can even buy a specialized instrument which reads, resets, and resyncs the TPMS units (Figure 2).

Fig 2: An instrument such as the Autel TS401 TPMS Relearn Tool can check, reset, reprogram, activate, and restore the individual tire sensors. (Image: Autel/Intelligent Technology Corp., Ltd.)

Conclusion

TPMS is another safety-related feature in a car and has definite benefits. However, as with all add-ons, it adds up-front cost and incurs significant replacement cost, and is another thing that possibly fails (both hard failure and intermittent). Successful implementation of TPMS is a significant engineering challenge which designers and vendors have met through advanced ICs and packaging techniques.

EE World related content

EEPROM-configurable IC enables easier development of TPMS modules
Smart Tires Pave the Road for Future of Autonomous Cars
When tire pressure monitoring gets smart
Miniature transponder coils target uses in tire pressure monitoring

 

References

TPMS Background and History

  • Schrader TPMS Solutions, “Schrader History”
  • CarID, “What Is The History Of Tire Pressure Monitoring Systems?”
  • Gregg’s Automotive, “The Story Behind Tire Pressure Monitoring System (TPMS)”
  • TMPS Direct, “A Brief History of TPMS”
  • Wikipedia, “Firestone and Ford tire controversy”

TPMS Operation

  • Tirebuyer, “What is TPMS (Tire Pressure Monitoring System)?”
  • Wikipedia, “Tire-pressure monitoring system”
  • Inertion, “The Better Way to Fill Your Tires”
  • TiresPlus, “Tire Pressure Monitoring System (TPMS)”
  • TMPS Direct, “TPMS Sensor Batteries”
  • Priority Tire, “TPMS 101: What Is it and How it Works?”
  • Car and Driver, “A Tire-Pressure Sensor Can Save You From Having a Blowout”
  • How Stuff Works, “How Tire Pressure Monitoring Systems Work”
  • Mechanic Base, “How to Reset Tire Pressure Light (TPMS) – By Car Model”
  • Autel, “MaxiTPMS TS401”
  • Subaru 2010, “How much does change in tire pressure affect tire circumference?”

TPMS ICs and Components

  • Melexis, “World’s smallest TPMS solution”
  • NXP, “Tire Pressure Monitoring Sensors”
  • NXP, “TPMS Selector Guide”
  • NXP, “A Global Solution for Tire Pressure Monitoring Systems”
  • Infineon, “Tire Pressure Sensor (TPMS)”
  • Infineon, “SP400-11-11 Automotive Tire Pressure Monitoring Sensor”
  • Infineon, “SP40PLUS Tire Pressure Monitoring Sensor”

 

You may also like:

  • TPMS
    The automotive Tire Pressure Monitoring System, Part 3: implementation
  • Tire Pressure Monitoring System
    The automotive Tire Pressure Monitoring System, Part 2: perspectives
  • Tire Pressure Monitoring System
    The automotive Tire Pressure Monitoring System, Part 1: the situation

  • Tire Pressure Monitoring Systems

Filed Under: Featured, Frequently Asked Question (FAQ), Pressure Sensor Tagged With: FAQ

Primary Sidebar

Featured Contributions

Fire prevention through the Internet

Beyond the drivetrain: sensor innovation in automotive

Sensors in American football can help the game

Select and integrate sensors into IoT devices

More Featured Contributions

EE TECH TOOLBOX

“ee
Tech Toolbox: Internet of Things
Explore practical strategies for minimizing attack surfaces, managing memory efficiently, and securing firmware. Download now to ensure your IoT implementations remain secure, efficient, and future-ready.

EE LEARNING CENTER

EE Learning Center
“sensor
EXPAND YOUR KNOWLEDGE AND STAY CONNECTED
Get the latest info on technologies, tools and strategies for EE professionals.

RSS Current EDABoard.com discussions

  • Powering a USB hub: safely distributing current from a shared power supply
  • RF-DC rectifier impedance matching
  • How can I get the frequency please help!
  • Elektronik devre
  • 12VAC to 12VDC 5A on 250ft 12AWG

RSS Current Electro-Tech-Online.com Discussions

  • 100uF bypass Caps?
  • Fuel Auto Shutoff
  • Actin group needed for effective PCB software tutorials
  • how to work on pcbs that are thick
  • compatible eth ports for laptop

EE ENGINEERING TRAINING DAYS

engineering
“bills

RSS Featured White Papers

  • 4D Imaging Radar: Sensor Supremacy For Sustained L2+ Vehicle Enablement
  • Amphenol RF solutions enable the RF & video signal chains in industrial robots
  • Implementing Position Sensors for Hazardous Areas & Safety

DesignFast

Component Selection Made Simple.

Try it Today
design fast globle

Footer

EE WORLD ONLINE NETWORK

  • 5G Technology World
  • EE World Online
  • Engineers Garage
  • Analog IC Tips
  • Battery Power Tips
  • Connector Tips
  • DesignFast
  • EDA Board Forums
  • Electro Tech Online Forums
  • EV Engineering
  • Microcontroller Tips
  • Power Electronic Tips
  • Test and Measurement Tips

SENSOR TIPS

  • Subscribe to our newsletter
  • Advertise with us
  • Contact us
  • About us

Copyright © 2025 · WTWH Media LLC and its licensors. All rights reserved.
The material on this site may not be reproduced, distributed, transmitted, cached or otherwise used, except with the prior written permission of WTWH Media.

Privacy Policy