What is emission maintenance (AU)?

Under Art. 35 VTS, emission maintenance comprises, for motor vehicles with a spark-ignition engine: checking the vehicle parts relevant for exhaust emissions and their adjustment according to the manufacturer’s specifications; if necessary their adjustment, repair or replacement; as well as a measurement of the content of carbon monoxide (CO), hydrocarbons (HC) and carbon dioxide (CO₂) in the exhaust.

The results are entered in the emission maintenance document. Modern vehicles with on-board diagnostics (OBD) continuously monitor the emission-relevant systems; the emission behaviour is moreover part of the official periodic inspection.

The legal basis for the emission maintenance obligation is the Traffic Rules Ordinance (VRV, Art. 59a); the technical implementation is governed by Art. 35 VTS.