5CF0E4 Mercedes Fault Code :
Read the description of 5CF0E4 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 '17R04: SCR exhaust aftertreatment AdBlue metering valve series resistor' has a short circuit to ground.