VOLVOUU All Engines (2010 Emissions) Fault Code: SPN 3051 FMI 7 PID: Catalyst 2 System Monitor

Conditions for diagnostic trouble code (DTC):
1) Insufficient aftertreatment diesel exhaust fluid (DEF) dosage

Observable symptoms
1) Smell of ammonia

Probable cause
1) Aftertreatment diesel exhaust fluid (DEF) dosage valve
2) Aftertreatment selective catalytic reduction (SCR) catalyst