The purpose of the TPMS (Tire Pressure Monitoring System) is to alert you when tire pressure is too low and could create unsafe driving conditions.
If the light is illuminated, it means your tires could be underinflated, which can lead to undue tire wear and possible tire failure. It’s important to understand the importance of proper tire inflation, and how TPMS can help you avoid a dangerous situation.
Both overinflation and underinflation can cause premature treadwear and possible tire failure. Overinflation can result in decreased traction, premature wear, and the inability to absorb road impact.
Overinflated tires will show premature wear in the center of the tread. On the other hand, underinflation will cause sluggish tire response, decreased fuel economy, excessive heat buildup, and tire overload.
An underinflated tire will show premature wear on both sides of the tread edges or “shoulders”.
If you’re learning about tire pressure sensors for the first time, finding the TPMS indicator on your dashboard is simple. It’s a horseshoe-shaped light with an exclamation point in the center.
What Does A TPMS Warning Light Mean?
Do you know what to do when the low tire pressure TPMS symbol illuminates? The first thing to do is manually check your tire pressures with a gauge and add air until the pressures reach the vehicle manufacturer specification.
You’ll find the correct pressure on the driver’s door jamb or in the owner’s manual, not on the sidewall of the tire- that’s the tire’s maximum pressure.
Keep in mind, your TPMS does not replace routine tire pressure maintenance. It’s a tool that can help alert you when pressure is low, but a tire may drop below proper inflation long before the TPMS warning light comes on.
The TPMS light comes on when the tire pressure gets too low or too high.
What Does a Tire Pressure Sensor Fault Message Look Like?
When a tire pressure sensor detects a problem with low tire pressure, it will send a signal to the car’s computer, which will then illuminate a light on the dash.
This light is generally bright yellow, and looks like an exclamation point (!), inside of a “U” shaped symbol. This is the drivers warning to check on their tires, as one may be flat or just low.
Common Causes of Tire Pressure Sensor Fault
TPMS failure can stem from various sources, including low battery voltage, damage from road debris, exposure to extreme temperatures, corrosion, sensor age, and faulty wiring. The TPMS sensor relies on battery power to function correctly; hence, low battery voltage can impair its operation.
Damage from road debris and exposure to extreme temperatures can compromise the sensor’s effectiveness. Corrosion, often due to environmental factors, can also lead to TPMS malfunctions. Sensor age is another factor, as older sensors may not function optimally.
Additionally, faulty wiring within the TPMS system can disrupt proper operation, causing inaccuracies in tire pressure readings.
Low Battery Voltage
Low battery voltage is a common culprit behind tire pressure sensor faults. When the battery level drops, it affects the TPMS system’s ability to function correctly, leading to inaccurate readings or complete failure.
This can trigger the tire pressure light on your dashboard. In extreme cases, low battery voltage may even cause a total system shutdown. To avoid this issue, it’s essential to regularly check your vehicle’s battery health and ensure it is in optimal condition.
Damage from Road Debris
Road debris poses a significant threat to tire pressure sensors, leading to potential faults. The sensors, located inside the tire or attached to the valve stem, are vulnerable to damage from sharp objects on the road.
Rocks, nails, or other debris can puncture the tire, causing not only a flat tire but also sensor damage.
This damage can result in inaccurate readings or complete sensor failure, triggering the tire pressure sensor fault alert.
To prevent this, avoiding debris-filled roads whenever possible, installing protective covers, or opting for sensors that are more resilient to external elements can help maintain sensor integrity. Regular inspections can also help detect any early signs of damage.
Exposure to Extreme Temperatures
Exposure to extreme temperatures can significantly impact tire pressure sensor function. High temperatures, especially in summer, can accelerate battery depletion in the TPMS sensor, leading to erratic readings.
Conversely, severe cold can cause the tire pressure to drop, triggering false alerts. These temperature fluctuations stress the sensor, potentially causing premature failure.
To mitigate this, park in shaded areas during hot weather and ensure proper insulation in freezing conditions. Monitoring tire pressure regularly and addressing fluctuations promptly can help prevent sensor damage due to extreme temperatures.
Regular maintenance and temperature-conscious driving habits are essential for optimal TPMS performance.
Corrosion
Corrosion is a common culprit behind tire pressure sensor faults. When metal components within the sensor are exposed to moisture or harsh chemicals, corrosion can occur, leading to malfunction.
The buildup of rust and corrosion can disrupt the sensor’s ability to accurately measure air pressure, triggering false alerts or a complete failure of the TPMS system.
It is crucial to regularly inspect and maintain the sensors to prevent corrosion-related issues.
Cleaning the sensors and ensuring they are properly sealed can help mitigate the risks associated with corrosion, prolonging the lifespan of your TPMS system.
Sensor Age
Sensor age is a crucial factor in tire pressure sensor faults. Over time, sensors can weaken, leading to inaccurate readings or complete failure. Aging sensors may struggle to maintain communication with the vehicle’s TPMS system, triggering warning lights.
As sensors age, they become more prone to signal delays or malfunctions, impacting the overall effectiveness of the TPMS. Regularly checking and replacing sensors, especially in older vehicles, can help prevent potential issues related to sensor age.
Keeping track of the sensor’s lifespan and proactively replacing them when necessary ensures reliable tire pressure monitoring and safe driving experiences.
Faulty Wiring
Frequently, faulty wiring can trigger tire pressure sensor faults. This intricately connected system relies on accurate data transmission for seamless operation. In cases where wiring suffers damage or degradation, the communication between the sensors and the vehicle’s TPMS system can be compromised, leading to misleading pressure readings or system malfunctions.
Understanding the wiring components and ensuring their integrity is crucial in preserving the reliability of TPMS alerts.
Proper maintenance and periodic checks can help detect wiring issues early, preventing potential failures that could disrupt the optimal functioning of the tire pressure sensor system. Addressing wiring concerns promptly can save time and money on potential repairs.
How to Troubleshoot TPMS Faults
Before you rush off to the mechanic, there are a few things you can try to troubleshoot your tire pressure sensor fault. Who knows? You might just save yourself a trip to the shop.
Step 1. Check Your Tire Pressure.
I know, I know. It sounds obvious, but start here. Use a reliable tire pressure gauge to check all four tires, including the spare if your vehicle has a sensor there too. Sometimes, the simplest solution is the right one.
As little as 5 PSI under the manufacturer recommended pressure can cause the dash warning light to illuminate. The manufacturer recommended pressure can be found in the owners manual, or on a sticker located on the drivers side doorjamb.
Step 2. Take a Short Drive.
Sometimes, sensors just need a little wake-up call. Take your car for a short spin around the block. The motion might help the sensors reset and start communicating properly again.
Step 3. Consider Recent Services.
Did you recently have your tires rotated or changed? The sensors might need to be reprogrammed. Some vehicles do this automatically after driving for a while, others need a technician’s touch.
Contact the tire/service center and explain the situation. They may recommend driving a bit longer for the sensor(s) to be “relearned” or may simply ask you to drive back to them so a tech can look into it.
Step 4. Check for Wheel Damage.
Take a good look at your wheels. Any visible damage to the rims could be affecting the sensors. While you’re at it, check the valve stems as well.
Step 5. Try a Manual Reset.
Some vehicles have a TPMS reset button. Check your owner’s manual for its location (often under the steering wheel) and the proper reset procedure. It might just clear up the fault.
Step 6. Battery Check.
If your car has been sitting for a while, a low battery can sometimes trigger sensor faults. Make sure your car’s battery is fully charged.
If none of these steps solve the problem, it’s time to bring in the pros. They have specialized tools that can communicate directly with your TPMS sensors to pinpoint the exact issue.
To Replace or Not to Replace
If checking and adjusting the tire pressure to within the proper specs does not remedy the problem, chances are good replacing the tire pressure sensor is necessary. The failed sensor can be identified using an OBD2 scanner, or through the vehicle’s dashboard computer options, depending on the model.
While having an automotive scan tool will let you diagnose the problem yourself, you can always have a local tire or repair shop perform a scan to quickly identify which sensor has failed. The battery life of these sensors typically ranges from 5 to 10 years.
TPMS Sensor Replacement Procedure
In order to replace a failed tire pressure sensor, the wheel with the bad sensor must have the tire dismounted. Once the tire is off the rim, the old sensor can be removed and the new one installed.
After the new sensor is put in the rim, the tire will be remounted and inflated. Then comes reprogramming so the car’s computer will recognize it.
Since most car owners don’t have the capability to dismount and remount a tire, a trip to the local tire shop is necessary. Fortunately, the process isn’t very expensive and you can usually purchase the TPMS sensor cheaper on your own to save some money.
Sensing/Reprogramming the Sensor
The reprogramming process varies for each vehicle’s make and model. Some cars require a certain amount of mileage to be put on the new sensor for the computer to recognize it, usually just a couple miles.
Other vehicles must be reprogrammed using the same scanner that found the bad one. The scanner programs the sensor’s signal to the car’s computer so the two can communicate. Without this, the dash light will stay illuminated because the computer can’t read the new sensor, making reprogramming a crucial part of the replacement.
TPMS Sensor Replacement Cost
The price of a TPMS sensor replaced at a dealership is usually between $125 and $200 per unit.
We phoned a local Subaru dealer who told us the price was $171 for a Forester’s sensor and that the cost to replace the sensor and then remount and balance the wheel brings the total cost to about $210.
A local Ford dealer we spoke to told us the price of the sensor in a Ford F-150 is $182 and that the mounting and balancing bring the price to just over $200.
By contrast, Jay from Boston Mobile Tire told us, “We charge $40 per sensor, which includes installation and programming during a tire-off service, add $50 labor per tire if we’re just doing a “sensor only” service as we still need to break down the tire and rebalance, etc.”
The best time to do a TPMS sensor replacement is when you are buying new tires since the rubber will be coming on and off anyway.
Can I Still Drive My Car?
Driving with a faulty TPMS can compromise your safety on the road. A malfunctioning tire pressure sensor may lead to inaccurate readings, potentially causing a flat tire or poor fuel economy.
The TPMS light might not warn you of actual tire failures, risking costly repairs. Furthermore, driving without a properly functioning TPMS system could result in decreased fuel efficiency and handling issues.
Ignoring the warning signs of a faulty TPMS can lead to unsafe driving conditions. To ensure your well-being and vehicle performance, address any tire pressure sensor faults promptly to avoid putting yourself at risk while behind the wheel.
Who’s Going to Fix It?
Choosing a place to have a repair of any sort done is solely up to the owner of the vehicle, and sensor replacement is no different! Of course, it is always recommended to choose a repair shop that is trustworthy and reputable. Avoid those shady places!
However, when it comes to tire pressure sensors, a big name dealership is not always the best choice either. A local tire shop should have the capability and knowledge to replace the sensor correctly.
Be sure to inquire about labor and part warranty when having any kind of work done at a shop. No one wants to spend money on a repair, just to find out the part was faulty or the labor done wrong.