Tire Pressure Monitoring System (TPMS) | Guide

A tire pressure monitoring system (TPMS) can detect tire loss early, thereby reducing the risk of typical consequences: increased braking distance, tire overheating, accelerated and uneven wear, and the risk of a blowout at high speed. Essentially, it’s one of the most accessible safety tools available: a warning is issued, the tire pressure is checked, the cause (puncture, valve leak, seasonal cold) is determined, and the problem is corrected before it leads to an emergency.

Based on service calls, the indicator most often illuminates not because of an "electronic failure," but because of a slow loss of pressure or a change in air temperature. As the weather gets colder, tire pressure drops, and the TPMS is one of the first to respond. If the signal appears while driving, it’s wise to slow down, evaluate your handling, and measure the pressure with a pressure gauge as soon as possible — this is more reliable than relying on the tire’s appearance.

How the system is structured and what types are there

Two basic control principles are used in vehicles: direct and indirect. Direct pressure is measured by tire sensors, while indirect pressure is measured by the system using ABS/ESP data and, based on wheel speed, detects a potential pressure drop (due to changes in the effective radius).

• Direct TPMS – each wheel has a self-powered sensor that measures tire pressure (often also temperature) and transmits the data to the electronic unit. Pros: high accuracy, ability to view tire pressure for each wheel. Cons: higher cost, limited battery life, and often requires pairing/training of the sensors.
• Indirect TPMS – no separate pressure sensors; the system compares wheel rotation speed and alerts you to potential pressure loss. Pros: cheaper, no sensors in the wheel that can fail. Cons: doesn’t display precise bar/kPa readings, sometimes triggers late, and requires proper calibration after tire inflation or rotation.

In many countries (including the EU market), TPMS has become mandatory for new vehicles as part of regulatory requirements. Specific requirements vary by year and region, so if in doubt, it’s best to consult your model’s owner’s manual.

What to do if the pressure indicator lights up

1. Assess the car’s behavior : pulling to the side, vibrations, poor steering response, or "floating" are reasons to stop as soon as possible in a safe place.
2. Check the tire pressure with a gauge when the tires are cold (either after parking or after a leisurely drive of 2-3 km). The recommended pressure can be found on a sticker on the door pillar/door frame, on the fuel filler flap, or in the owner’s manual.
3. Inspect the wheel : there may be a screw, cut, crack, hernia, as well as traces of air leakage at the valve stem (including a wet trace from sealant or soap solution).
4. Inflate the tire to the recommended level and check to see if the pressure drops again within 24 hours. If the pressure continues to drop, a leak detection and repair are required.
5. Perform a reset/calibration if required by the system design (especially for an indirect system). This function is usually found in the on-board computer or multimedia menu.

Important: If your tire is noticeably flat or you suspect sidewall damage, it’s best to install a spare tire or space-saver and drive to a tire shop. Driving with low tire pressure quickly damages the tire carcass and can damage the rim.

Why the system may be lying and how to check it

The most common causes of false alarms or unstable readings are:

• Temperature : It got colder at night, causing the pressure to drop, triggering a warning. Some of the pressure "returns" after warming up, but the warning shouldn’t be ignored.
• Indirect control calibration is lost after inflation, wheel rotation, tire replacement, or size change.
• Sensor failure in the direct system: battery discharge, mechanical damage, oxidation of contacts.
• Incompatible sensors when installing a second set of wheels: a common problem with universal solutions that lack proper firmware or vehicle-specific settings.

The test is straightforward: compare the TPMS data with the readings from a working pressure gauge. Accuracy tolerances vary between manufacturers, but if the discrepancy is consistently large or the readings fluctuate, it’s worth running a diagnostic scan and checking for errors on each sensor.

Tire Changes, Seasonal Wheels, and Sensors: Practical Considerations

In direct monitoring systems, sensors are typically located inside the wheel — on the valve stem or on the mounting strap. When installing tires, it’s important to inform the mechanic in advance about the presence of a sensor; improper installation or removal can damage it. If a second set of wheels is used, it’s often more convenient to have a second set of sensors and perform the correct alignment once — this speeds up seasonal changes and reduces the risk of errors.

The battery in most sensors is maintenance-free: when the battery is discharged, the entire sensor is replaced. The actual service life is typically several years and depends on mileage, operating conditions, and data transmission frequency. When the battery is about to discharge, the system often detects an error for a specific wheel.

How to maintain correct tire pressure and extend the life of your tires

• Check your blood pressure at least once every 2–4 weeks and always before a long trip.
• Measure the pressure when cold and follow the vehicle manufacturer’s recommendations, not the maximum pressure indicated on the sidewall of the tire.
• After repairing a puncture, replacing a valve stem or working on a disc, recheck the pressure after 24 hours.
• Don’t ignore a slow leak: it’s what most often leads to overheating, poor handling, and accelerated tread wear.

If you need official information on tire pressure standards, indications, and calibration procedures, the most reliable sources are the owner’s manual for your specific vehicle and the manufacturer’s service materials. Publications from specialized organizations and regulators responsible for road safety are also helpful for understanding the general principles of TPMS operation.