What is the difference between external and internal car tire pressure monitors?

[Kristin]

Car tire pressure monitors differ in installation methods between external and internal types: external monitors have sensors installed on the outside of the tires, while internal monitors have sensors installed inside the tires. The functions of tire pressure monitoring are: 1. Preventing accidents; 2. Extending tire service life; 3. Reducing wear on the suspension system. Tire pressure monitoring automatically checks tire pressure in real-time during driving and alerts the driver to leaks or low pressure to ensure driving safety. The working principle involves an internal sensor mounted on the tire hub, which includes a bridge-type electronic pressure sensing device that converts pressure signals into electrical signals and transmits them via a wireless transmitter.

[NolanFitz]

I've been driving for over a decade. The external tire pressure monitor is the type that directly attaches to the tire valve stem, and you can install it yourself in just a few minutes, which is super convenient for DIY beginners. However, the issue is that it's exposed outside, making it prone to theft or getting knocked off, especially when parked in public places—I always worry about losing it. In summer, it might also cause wind noise or false alarms because it's exposed to dust and temperature changes. In contrast, the internal type is hidden inside the tire and requires a professional shop to remove and install the wheel. It takes more time upfront, but once installed, it's extremely stable—no worries about theft or affecting driving balance. It's also more accurate than the external type, providing better monitoring of tire pressure and temperature, making it more reliable for long-term use, especially suitable for long-distance or high-speed driving enthusiasts. However, it's slightly more expensive, and during maintenance, you need to remind the technician not to damage the sensor. Overall, if you prioritize convenience, go for the external type; if you value safety and durability, choose the internal one.

[Cunha]

From a practical perspective, external tire pressure monitoring systems are extremely easy to install. Just purchase a set online and screw them onto the valve stems yourself—it takes only minutes and saves the hassle of visiting a shop. The initial cost is also low, making it suitable for budget-conscious drivers. However, they are prone to dirt and damage, and readings may become erratic after rain or rough roads. At high speeds, the strong vibrations can sometimes affect tire balance, causing the car to shake.

In contrast, built-in systems require a small investment for professional installation at a repair shop, which is a bit more involved. But once installed, they can last for years, are highly durable, offer top-notch accuracy with minimal false alarms, and have strong anti-theft features since they can't be easily removed. Additionally, the built-in sensors directly contact the tire's internal space, allowing precise monitoring of temperature changes—critical for safe driving, such as avoiding blowout risks. Maintenance-wise, you need to be careful not to damage the sensor during tire changes, but this is a minor trade-off.

[LaCali]

From personal experience, built-in tire pressure monitoring is clearly more reliable. Installed inside the tire, it's free from external interference, provides accurate data, and is durable, with minimal concerns about wind noise or theft. It also helps maintain tire balance for smoother driving. External sensors are quick to install but too exposed—easily stolen when parked or prone to false alarms from freezing, especially troublesome in northern winters, plus their batteries last at most two years before replacement. Built-in sensors, though initially more expensive (costing an extra hundred or two for professional installation), offer five to six years of worry-free and secure use. Maintenance shouldn't be overlooked; tire changes or rotations require professional handling. Overall, external sensors suit temporary needs, while built-in ones are a long-term investment.