Why does the exhaust brake indicator light sometimes come on?
2 Answers
Exhaust brake indicator light sometimes comes on means the exhaust brake system is working. If you don't want to use the exhaust brake, you can manually turn it off. The exhaust brake used in vehicles mainly serves as an auxiliary function. When the vehicle is in motion, the exhaust brake indicator light will illuminate when the driver steps on the brake pedal or clutch pedal, and it will turn off when released. The exhaust brake system is mainly used in large trucks. The working principle of the exhaust brake is: a regulating valve is installed on the engine's exhaust pipe, and the pressure of the exhaust stroke is increased by opening and closing this valve, using the generated negative pressure to obtain braking force. With the assistance of the exhaust brake, the vehicle's braking performance can be improved.
I often encounter the strange phenomenon of the exhaust brake indicator light suddenly turning on during long-distance driving, usually occurring after rainy days or bumpy mountain roads. The light indicates an issue with the exhaust brake system, possibly due to a damp sensor or loose wiring causing false alarms. The exhaust brake helps slow down trucks when descending slopes, and if the light is on, it may not be functioning, increasing brake burden and fuel consumption. I recall once discovering oxidized connectors during an inspection, and the problem disappeared after cleaning them. For safety, if the light comes on, slow down and drive cautiously, then visit a repair shop as soon as possible for a check-up. Don’t ignore it—minor issues can escalate and endanger driving. Simple maintenance, such as regularly cleaning the sensors, can prevent such problems.
