You're going to have to be more specific with your question. There are many components to the emissions control system.
Emissions.
VSC=Vehicle Stability Control, or basically traction control system
An emissions control system is typically going to refer to a system that limits certain pollutants (emissions) given off by a vehicle. A catalytic converter is one example.
The 2003 Cadillac DeVille typically has two catalytic converters. One is located on each side of the exhaust system, as the vehicle is equipped with a V8 engine. These converters are part of the vehicle’s emissions control system, helping to reduce harmful exhaust emissions.
it's talking about the emissions system. it is probably just a loose gas cap
Electronic Vacuum Regulator which is part of the EGR emissions control system.
Have vehicle scanned to determine the problem - usually in the emission control system,
Trouble code P0446 means: Evaporative Emission System Vent Control Circuit
Have vehicle scanned to determine the problem - usually in the emission control system,
I have a 2000 I30 and there is a map/diagram of the emissions control system including the EGR system on the underside of the hood placed there presumably by the manufacturer.
There is a problem somewhere in an emissions control system. Get it fixed.
That is the first time I have heard the term auxiliary emissions control, a vehicle only ever has one emissions control system. Could you provide an obd trouble code so a proper diagnosis can be given