5DF0E3 Mercedes Fault Code :
Read the description of 5DF0E3 in ACM21T and the engine lights up for ACM21T Aftertreatment Control Module code, there are some possible causes for it.
The output of component '17Y06: AdBlue metering unit valve' for the power supply of component '17Y03: SCR exhaust aftertreatment AdBlue metering valve' has a short circuit to positive.