What does it mean when the car detects pressure loss?

[McJune]

The pressure loss displayed on the dashboard indicates insufficient tire pressure, and you should check the air pressure of all four tires. Here are the detailed explanations: 1. Hazards of high tire pressure: Reduced rolling resistance. When encountering sharp objects such as nails or glass on the road, they can easily puncture the tire. Such impacts can cause internal cracks and explosions, leading to tire leaks. 2. Indirect tire pressure monitoring: The working principle of indirect tire pressure monitoring is that when tire pressure decreases, the vehicle's weight causes the rolling radius of the wheel to become smaller, resulting in the wheel rotating faster than others. Tire pressure can be monitored by comparing the speed differences between tires. Indirect tire pressure warning systems essentially rely on calculating the rolling radius of the tire to monitor tire pressure.

[DelJourney]

I was really panicked when I encountered this issue last time. The tire pressure warning light suddenly came on, and upon checking, I found a screw stuck in the right rear tire. Nowadays, new cars come with tire pressure monitoring systems, and a pressure loss is most likely due to a tire leak. There are generally three common scenarios: a nail puncture, a leaking valve stem due to aging, or a deformed wheel rim edge causing a poor seal. Once, while helping a neighbor check their tires, I discovered a small cut on the sidewall from scraping against a curb, which caused a slow leak that took three days to trigger the alarm. A quick reminder to everyone: the spare tire might also have a tire pressure sensor, so don’t forget to reset the system after changing a tire. The safest approach when the warning light comes on is to slow down, pull over, and inspect immediately. Last time, my friend kept driving and ended up ruining the wheel rim.

[OClara]

With twenty years of car repair experience and having encountered over a thousand cases of tire pressure warnings, let me share some practical insights. Besides obvious punctures, a 2.3-degree temperature drop in winter can reduce tire pressure by 0.1 bar, triggering the yellow warning light on the dashboard. German cars are particularly sensitive; sometimes even hitting a speed bump too hard can cause a false alarm. Once, a customer thought the sensor was faulty, but upon disassembly, we found a crack on the inner side of the rim—completely invisible without removing the tire. Slow leaks are the most dangerous; I’ve seen cases where a leaking valve stem caused pressure to drop from 2.5 to 1.8 over two months. Here’s a handy tip: when the tire pressure light flashes, pull over safely and feel the wheel rims—the one noticeably hotter is definitely leaking.

[Reagan]

Don't panic when encountering a tire pressure warning as a beginner. I just learned how to handle it last week. First, open the car door and check the label on the B-pillar to find the standard tire pressure value. Use a tire pressure gauge (costs about ten yuan) to measure all four tires - the one significantly lower is the problematic tire. Last week, my front left tire was at 2.0 while others were at 2.5, and the car wash shop found a cracked valve stem. The tire repair technician said modern nails come with adhesive coating - they won't cause immediate air loss when punctured, but might lead to blowouts during high-speed sharp turns. Underinflated tires also significantly increase fuel consumption - about 0.5 liters more per 100 kilometers. Remember to press the SET button to reset after tire repair, otherwise the warning light will stay on.