Why does the tire pressure monitoring suddenly display bar?
3 Answers
When the car displays bar, it indicates low tire pressure, and you need to check if the tire is leaking. Below is an introduction to bar-related content: Conversion: The general tire pressure for cars is around 2.5bar, where 1bar equals 100kpa. Unit: Both bar and kpa commonly seen on vehicles are units for measuring tire pressure, and the tire pressure display is used to show the current tire pressure. Lifespan: Both excessively high and low tire pressure can affect the tire's lifespan. When the tire pressure is too low, the tire body expands, making the sidewalls prone to cracking. It also increases the tire's contact area with the ground, accelerating tire wear.
I've been driving for many years, and there are several common reasons why the tire pressure monitoring system suddenly displays BAR values. Temperature changes cause tires to expand and contract—for example, when transitioning from summer to autumn, the drop in temperature can reduce tire pressure, triggering an alarm to display BAR. It could also be due to a nail puncture or a minor leak in the valve, causing unstable pressure, which prompts the system to automatically show BAR units as a reminder to check. Some vehicles have sensors with limited battery life; after five or six years, depleted batteries may lead to inaccurate data and false BAR readings. I usually use a portable pressure gauge to manually check tire pressure monthly, maintaining the manufacturer-recommended BAR range. If the cause is unclear, it's best to visit an auto repair shop immediately for diagnosis to avoid long-term neglect leading to tire wear or handling risks—this is more reliable than just relying on the dashboard. Developing a habit of regular maintenance can significantly reduce sudden malfunctions.
As a car enthusiast, I know that BAR is a unit for tire pressure, and its sudden display often indicates the system is monitoring pressure anomalies in real time. For example, high sensor sensitivity can easily trigger BAR display due to tire pressure fluctuations under low temperatures or high-speed driving. It could also be due to sensor signal interference, such as strong nearby magnetic fields or electrical shorts causing false BAR readings. It's normal for the BAR value to briefly appear when the car starts as the screen refreshes. I've researched using an onboard OBD diagnostic tool to read fault codes, which can accurately confirm the cause. While driving, paying attention to unusual tire noises or slight tilting can help detect issues early. Regularly replacing sensor batteries or calibrating the system is key to prevention, as neglecting small problems can lead to costly major repairs.
