The Diesel Exhaust Fluid (DEF) system in your 2014 Sprinter van is crucial for emissions control. Understanding the DEF warning messages and knowing how to maintain the system properly can prevent costly repairs and keep your van running smoothly. This guide will clarify the DEF warning system in your Sprinter and provide best practices for DEF maintenance.
DEF Warning Messages: Understanding the System
Your Sprinter’s onboard computer monitors the DEF level and provides warnings when it’s low. The owner’s manual outlines a two-stage warning system:
- First Warning: Triggered when the DEF level drops below 1.5 US gallons (5.5 liters). A warning message displays, and a tone sounds. The manual suggests that, under normal driving conditions, you have approximately 1000 miles (1600 km) of driving range remaining.
- Second Warning: Triggered when the DEF level reaches a reserve mark of 0.8 US gallons (3.0 liters). A second warning message appears, accompanied by a distinct warning tone sequence. At this point, you have approximately 1200 miles (1900 km) of driving range remaining and a limited number of engine starts (around 16).
There seems to be a contradiction in the manual regarding the remaining mileage after the first warning. However, the critical takeaway is that you must refill the DEF tank as soon as possible after receiving any warning message. Ignoring these warnings can lead to reduced engine power and eventually prevent the engine from starting.
Best Practices for DEF Maintenance in Your Sprinter Van
To avoid DEF-related issues, proactive maintenance is essential.
- Regular Top-Offs: The owner’s manual recommends refilling the DEF tank “regularly.” Don’t wait for warning messages. Topping off the DEF tank every 500-1000 miles ensures the system functions correctly and prevents potential problems.
- Using Quality DEF: Mercedes-Benz sells pre-packaged DEF in convenient containers designed for easy refilling. While more expensive than bulk DEF, these containers minimize spills and contamination. If you opt for bulk DEF, ensure it’s from a reputable source and stored properly to prevent crystallization.
- Cleaning Up Spills: DEF can corrode certain materials. Immediately rinse any spills with water.
- Preventing Contamination: Keep the DEF tank and filling equipment clean and free from debris to avoid contaminating the DEF. Crystallized DEF can also cause issues.
Conclusion: Keeping Your Sprinter on the Road
The DEF system in your 2014 Sprinter van requires attention and regular maintenance. Understanding the warning system and following these best practices will prevent costly repairs and ensure your van remains operational. Don’t hesitate to consult a qualified Sprinter specialist if you have any concerns or encounter problems with the DEF system. Prioritizing DEF maintenance will keep your Sprinter running smoothly for years to come.
