What does the 3363+16 fault code mean?
2 Answers
3363+16 fault code refers to the Catalyst 1 Tank Heater Circuit High. Causes: Coolant pipe direction reversed, tank heater control valve reversed, post-processing level temperature sensor reversed; tank heating valve stuck open; incorrect heating valve model used. Methods: Check whether the coolant pipes, tank heater control valve and post-processing level temperature sensor are reversed, perform "Diesel Engine Urea Injection System Heater Test", check whether the tank heating valve is working normally. If blockage or mechanical failure is found, repair or replace the heating valve. Check whether the tank heating valve model matches the ECM model.
I was quite nervous when I encountered a fault code similar to 3363+16, as it sounds like something went wrong with the engine management system, usually indicating a crankshaft position sensor or related circuit failure. For example, if the sensor signal becomes unstable, it affects the precise timing of engine ignition. If it fails, the car may experience difficulty starting, poor acceleration, or even stall on the road, which is very dangerous. I suggest not driving in a hurry and finding a quiet place to park and check if any other warning lights on the dashboard are illuminated, such as a flashing engine light, then immediately contact a repair shop for a diagnostic scan. Regular maintenance is also important—keep the sensor connectors clean and free from dust or moisture to avoid false alarms.
