Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Cleaning Procedure
The diesel exhaust fluid (DEF) system is part of the emission system for this vehicle and must be serviced while observing extreme care to prevent foreign contamination of any kind from entering this system. If extreme care is NOT taken to prevent contamination from dirt, debris, fluids other than DEF, etc., reduced performance and/or damage to the DEF system may result.
- Cleanliness of the diesel exhaust fluid (DEF) system is crucial to ensure proper operation. Before opening any part of the DEF system, ensure connections and joints are thoroughly clean and dry of any dirt, debris or other contaminants. Use only low pressure water and low pressure air, as directed.
- Diesel exhaust fluid (DEF) will have a tendency over time to develop areas of dried crystallization residue. Crystallization residue is a normal process for this fluid. Dried DEF crystallization residue can be wiped away or flushed away with clean water, depending on location of the crystallization.
- Ensure the ignition is OFF.
- Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle .
- Using only a Low pressure clean water hose, spray the upper surfaces of the Diesel Exhaust Fluid (DEF) Tank (1) and pump supply module, the injection hose and the fill hose assembly, to remove all dirt and debris.
- Using only a low pressure air wand or air gun, direct air along the same surfaces to both dry and remove any further contaminants.
- Using a clean white shop towel, carefully dry connections and joints by hand to ensure dryness and cleanliness.
NO RELATED
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.