What is the SPN3226 fault?

[VonJasmine]

SPN3226 fault code indicates that the emissions are not up to standard, and the urea supply system needs to be checked for proper functioning. Below is the relevant introduction: 1. Name Origin: The technical name for automotive urea is Diesel Exhaust Fluid (DEF), commonly referred to in China as automotive urea, vehicle urea, or vehicle denitrification agent. Automotive urea solution was first used in Europe, where it is called AdBlue, while in North America, it is known as DEF (Diesel Exhaust Fluid). It should be noted that there are urea manufacturers abroad with AdBlue and DEF certifications, which adhere to strict international standards, whereas very few domestic enterprises in China have obtained AdBlue or DEF certification. 2. Composition: Automotive urea solution is a colorless, transparent, and clear liquid with a concentration of 31.8% to 33.2%, used for reducing NOx emissions. Currently, the automotive urea solution in use is generally composed of 32.5% high-purity urea and 67.5% deionized water.