What does it mean when the SCR light is on in a truck?
2 Answers
SCR light refers to the Selective Catalytic Reduction system. The following are the reasons why the SCR light is on: The SCR light being on indicates a fault in the Selective Catalytic Reduction system. Here are the reasons that can cause the catalytic reduction system to malfunction: 1. Due to sensor damage. 2. Loose sensor connector. 3. Short circuit or related wiring harness issues. Here is an introduction to the principles of the Diesel Selective Catalytic Reduction (SCR) system: 1. It is used to remove nitrogen oxides from diesel engine emissions. 2. Under high-temperature conditions, the urea injection unit sprays a urea aqueous solution into the exhaust pipe. 3. Urea hydrolyzes at high temperatures to release ammonia, which reacts with nitrogen oxides in the exhaust gas in the SCR catalyst through redox reactions. 4. Nitrogen and water are regenerated, thereby achieving the goal of reducing nitrogen oxide emissions from diesel engines.
The SCR light illuminating on a truck typically indicates an alert from the emission control system, notifying you to check the urea solution supply or system operation. Having driven trucks for nearly a decade, I've encountered this situation several times. The most common cause is low AdBlue fluid level: the warning light activates when the urea is depleted. If not replenished promptly, the vehicle may enter a speed limitation mode, affecting operation. Other potential issues include a clogged urea pump or faulty sensors, all requiring immediate attention. Last time my light came on, I promptly refilled AdBlue at a service station, resolving the issue without complications. Remember, emission regulations are stringent; neglecting this may lead to fines or performance degradation. Developing a habit of monthly urea tank level checks can prevent numerous troubles.
