Underbody lights are lighting fixtures installed on a vehicle's chassis that add a unique visual flair at night. Beyond their decorative appeal, they serve an important warning function by indicating the vehicle's position-whether moving or parked-to pedestrians and other drivers, thereby helping to reduce the risk of accidents.
There is a wide variety of underbody lights available; early neon versions have largely been replaced by LEDs, which offer longer lifespans, energy efficiency, and higher brightness. Installation methods generally fall into two categories: adhesive-backed and screw-mounted. Adhesive types require peeling off a protective film and sticking the light in the designated spot, whereas screw-mounted types require drilling holes in the chassis to match the light's mounting points and securing them with screws. Proper power connection is crucial during installation, ensuring the positive and negative terminals are correctly secured.
To avoid failing the annual vehicle inspection, one can install a temporary switch, connecting the red and black wires in parallel using a dedicated power cable. After installation, the lights should be tested for proper operation before being permanently secured with screws. Prices vary; for example, a 30cm soft LED strip costs around 28 yuan, a front grille/underbody strip is 35 yuan, a 5-meter high-brightness waterproof SMD strip is 22 yuan, and a wireless remote-controlled light with music/sound activation is 57 yuan.
When installing underbody lights, it is essential to choose high-quality, waterproof LEDs to ensure safety and proper circuit function. Installation is recommended on the front, rear, or sides of the chassis, with weekly inspections. When installing LED strips, ensure shock resistance, select appropriate resistors and voltages, verify correct polarity (positive/negative connections), and clean the underbody surface before securing the lights with automotive-grade silicone adhesive.
However, in my country, installing optoelectronic devices that interfere with road traffic safety is prohibited; installing underbody lights may violate traffic regulations, depending on local laws and the judgment of traffic police. Therefore, one should fully understand the relevant regulations before installation to avoid unnecessary trouble.
Chassis rust protection is a key measure for extending a vehicle's lifespan and reducing interior noise. Many manufacturers apply rust-proofing treatments-such as protective paint or "chassis armor" coatings-at the factory. Since factory-applied treatments are generally superior to aftermarket options, new cars usually do not require immediate additional rust-proofing. You might consider applying an anti-rust treatment once the new vehicle has covered approximately 50,000 kilometers; however, if the vehicle is frequently driven in harsh road conditions or in humid, rainy regions, you may want to adjust the maintenance schedule accordingly.
A proper underbody anti-rust treatment should provide uniform coverage across the entire chassis, ensuring that water does not adhere to the surface. It is advisable to have this service performed at a professional auto detailing center and to avoid the use of alkaline cleaning agents. Popular "underbody armor" products on the market can effectively minimize damage from gravel impacts, prevent corrosion and rust, and provide sound insulation; however, as the application process is demanding, it is important to choose a reputable service provider.
The effectiveness of underbody rust protection depends on the driving environment. For vehicles used in areas with high salt levels and humidity-such as coastal regions-applying an aftermarket anti-rust treatment is worth considering, provided high-quality materials are used. Conversely, in dry climates where de-icing agents are not used on the roads, skipping this treatment is generally not a major issue. In general, vehicles in higher price brackets (e.g., over 200,000 RMB) tend to have superior factory rust protection, whereas lower-priced vehicles may have more basic rust-proofing measures.