The Engine Control Module (ECM) has detected that the heating element inside the Diesel Exhaust Fluid (DEF) dosing unit is drawing incorrect current or remains active when it should be off. This usually implies an internal short circuit or a malfunction within the dosing unit's integrated heater electronics.

Let me know your thoughts in the comments. Thanks in advance! 👇

A "turtle" icon or "Engine System Reduced Performance" message may appear, limiting speed and acceleration to protect the engine.