You have not mentioned for which state you need the notification. I assume that it is for Kerala because you are from Kozhikode.
Minimum wages for General Engg and automobile sector was last revised in 2009. The notification is in Malayalam and the same is attached.
For automobile industry, there has been a dispute about the basic Act under which the workers' service conditions fall. In the case of an establishment which is manufacturing automobiles, there is no doubt and the Factories Act will be applicable for such establishments. In the case of automobile dealerships, both the area labour officers as well as the Factory Inspector take the stand that this belongs to them. It is also without any doubt that if the establishment is just a showroom, the Kerala Shops and Commercial Establishments Act will be applicable to it whereas if in the same premises there is a service station, the provisions of the Factories Act should be made applicable to it. Though both the Acts provide for registration of establishments and ensuring safety, welfare, health of employees, the latter is a Central Act which will supersede over a state Act. As such if the dealer outlet has a service centre within the same premises, you need not bet registration under Shop Act but the licence under Factories Act is enough.