What Causes Brake Light Failure?
3 Answers
The causes of brake light failure include: 1. Brake system failure due to severe oil shortage caused by damaged brake fluid pipes; 2. Low oil level in the brake fluid reservoir leading to float sensor malfunction; 3. Severe wear of brake pads and breakage of embedded wires; 4. Short circuit in the brake warning system and vapor generation in the brake fluid lines. Below is an introduction to the brake system: 1. The brake system consists of a series of specialized devices that forcibly reduce the vehicle's speed. 2. The brake system is mainly composed of four parts: the energy supply device, control device, transmission device, and brake. 3. The main functions of the brake system are to decelerate or even stop a moving vehicle, maintain a stable speed for a vehicle going downhill, and keep a stationary vehicle from moving.
Once when I was driving on the highway, the brake lights suddenly stopped working, which was really scary. Common causes include a burnt-out bulb—older cars often have filaments that break over time, and replacing the bulb can fix the issue. Another reason could be a blown fuse, such as when excessive braking current on rainy days causes the fuse to burn out. Try opening the fuse box and replacing it with a new one from the car. Wiring faults are also common—loose or rusted wire connections can lead to poor contact, and short circuits or open circuits can cause the lights to fail. There’s also the issue of the brake switch; wear and tear on the switch under the pedal or a stuck relay can prevent the lights from working. I recommend stopping immediately to check if this happens, as rear-end collisions are more likely at night if the following car can’t see your brake lights. During regular maintenance, have a technician inspect the light conditions—safety on the road should never be taken lightly.
I find brake light failures quite annoying. As a beginner, I usually go straight to the repair shop. The most common reason is bulb aging - frequent braking naturally causes filaments to break easily. Blown fuses are also common occurrences, as sudden current surges melt them to protect the circuit. Poor contact or short circuits in wiring are quite prevalent too, caused by loose connectors or aged/broken wires. Additionally, relay failures or switch wear can interrupt signal transmission. For quick checks, I always start by measuring voltage changes with a multimeter to save time searching elsewhere. When parking, I make it a habit to check tail light brightness myself - early detection means early repair, preventing road hazards. Safety always comes first - don't lose big for small gains.