This unit describes the performance outcomes required to diagnose and repair faults in the emission control systems of light vehicles. It involves preparing for the task, selecting the correct diagnostic procedure, carrying out the diagnosis and the repair, performing post-repair testing, and completing workplace processes and documentation.

It applies to those working in the automotive service and repair industry. Emission control systems include those in light vehicles, light commercial vehicles, marine vessels or motorcycles. This unit does not apply to agricultural vehicles, heavy commercial vehicles or mobile plant machinery.