Fault code 06148, Renault diesel engine?

Got a 2004 Nissan Primastar 1.9dci which is the same as the Renault Traffic version. A warning light came on, this was scanned and 5 faults relating to the ERG valve, choke valve, and the mass air unit? appeared. All 3 parts were replaced and all but one of the codes were cancelled. 06148 [undocumented code] will not go away and we can't reset the warning light. Anyone know what 06148 refers too?