The Service Engine Soon Lamp On with Post Oxygen Sensor Faults Stored. The Service Engine Soon (MIL) lamp is on and the following faults are stored in the DME fault code memory. BN2000 (E-Series) vehicles: * 2D22: Oxygen sensor downstream of catalytic converter, electric: open circuit BN2020 (F-Series) vehicles: * 12AB04: Oxygen sensor downstream of catalytic converter, electric: open circuit * 12AC04: Oxygen sensor downstream of catalytic converter 2, electric: open circuit These faults may occur sporadically after a long MSA engine stop. Unfavorable DME software diagnostics (fault is erroneous) This software error affects vehicles produced from 3/2013 to 6/2013, as well as older vehicles which have been programmed during service work to a current integration level of Xxxx-13-03-5xx.