Which is Better: Internal or External Tire Pressure Monitoring?
2 Answers
From the perspective of safety and stability, internal ones are better. External tire pressure monitoring devices are easy to install, but their sensors are exposed to the outside environment year-round, facing more complex challenges, making them prone to being dislodged or stolen. Therefore, for car owners who frequently drive long distances, an internal tire pressure monitoring product is more suitable. TPMS (Tire Pressure Monitoring System) is divided into three types: direct, indirect, and hybrid. Below is an introduction to these three types: 1. Direct TPMS: Uses pressure sensors fixed in each wheel to directly measure the tire pressure. It employs a wireless transmitter to send pressure information from inside the tire to a central receiver module, which then monitors the tire pressure data for each tire. When the tire pressure is too low or there is a leak, the system automatically alerts the driver, who can then check the digital tire pressure readings for each wheel to see if there is any abnormality. 2. Indirect TPMS: Works in conjunction with the vehicle's Anti-lock Braking System (ABS). Its working principle is that when the pressure in a tire decreases, the vehicle's weight causes the rolling radius of that wheel to become smaller, leading to a faster rotation speed compared to other wheels. By comparing the speed differences between the tires, it achieves the effect of monitoring tire pressure. Its drawback is that it cannot indicate specifically which tire is in a high or low-pressure state, thus having certain limitations. 3. Hybrid TPMS: Requires the installation of two additional tire pressure sensors and a radio frequency receiver in the system, enabling it to monitor the status of each tire. However, it still lacks in terms of system reliability and flexibility, and it does not meet or is not suitable for the aftermarket.
When it comes to built-in and external tire pressure monitoring systems, as someone who frequently drives for deliveries across cities, I find that the built-in ones are more accurate with fewer false alarms. The sensors inside the tires directly monitor air pressure and temperature, providing stable readings even at high speeds. However, installation is a hassle—you have to go to a shop to remove and reinstall the tires, costing a few hundred bucks each time. Plus, the battery lasts only three to five years before needing replacement, which is another hassle. External monitors are much simpler—just order one online and screw it onto the valve stem; it takes just a few minutes to install yourself, and they’re a lot cheaper. But they’re easier to steal or damage, and exposure to wind and rain can degrade accuracy over time, sometimes requiring recalibration. If you often take long trips or prioritize reliability, I’d recommend built-in monitors. For convenience in daily commuting, external ones work just fine. Also, keep in mind that cold winter air lowers tire pressure, so expect more alerts from the monitor—just remember to regularly check the actual tire pressure.
