How to Troubleshoot When the Urea Warning Light Comes On?
3 Answers
Methods to troubleshoot when the urea warning light comes on: 1. If the vehicle experiences poor acceleration or white smoke from the exhaust pipe, professional equipment is needed to clean the urea crystallization inside the exhaust pipe; 2. If the vehicle's fault code indicates low urea pressure, it is necessary to replenish the urea; 3. If the engine torque is limited and the RPM cannot exceed 1800 per minute, the urea pump and sensor need to be replaced. Automotive urea is a high-purity transparent liquid with a faint ammonia odor, alkaline but non-toxic. Failure to load diesel exhaust fluid (DEF) or using impure or substandard DEF can cause the vehicle's engine to automatically reduce speed. Poor-quality DEF can contaminate the catalyst in the SCR catalytic reaction tank, leading to serious consequences.
When I first drove a diesel car, I often encountered the issue of the urea warning light coming on. Usually, it's because the urea fluid is insufficient—quickly check the fluid level at the filler port where there's a gauge. If it's below the minimum line, you need to add special urea fluid. Never use water or anything else as a substitute. If the light stays on after refilling, the sensor might be faulty. Try turning off the engine and restarting it to reset the system. If that doesn’t work, check if the urea pump or nozzle is clogged—any blockage will trigger the warning light. Remember to regularly top up urea during maintenance, typically checking every 10,000 kilometers or so. Otherwise, system restrictions may affect power and fuel consumption. If all else fails, take it to a professional repair shop to scan for trouble codes—don’t attempt random fixes to avoid damaging the emission system.
I believe the key to preventing the urea warning light from coming on is regular checks. I take a look at the urea tank level every week, and as long as it stays above the middle line, there's usually no issue. When the light comes on, don't panic—most of the time, it just means the urea is running low. Diesel vehicles need this liquid to reduce exhaust pollution, and the light alerts you when it's lacking. If the light doesn't go off after refilling, check the cleanliness of the urea injector; frequent short trips can lead to carbon buildup. Also, consider whether you've been using substandard urea—cheap products often cause sensor false alarms. For maintenance, I make it a habit to thoroughly clean the system components every six months, which saves a lot on repair costs. One more thing: if you ignore the warning light for too long, the vehicle may limit power or even speed, which is extremely dangerous on highways. Always address issues promptly.
