40F0FF Mercedes Fault Code :
Read the description of 40F0FF in MCM02T and the engine lights up for MCM02T - MCM Engine management (10A20) code, there are some possible causes for it.
Current fault codes are present in control unit '10A17 (Drive control (CPC) control unit 3)' which lead to a consequential fault in control unit '10A20 (Engine management control unit (MCM))'.