Import your vehicles
If you settle in Spain and you own a car, then you are required to exchange the number plate for a Spanish one. You have a period of 60 days for this.
After the 60 days, the vehicle is no longer regarded as part of your move and you must pay import duties.
The application for registration is done at the Jefatura Provincial de Tráfico.
http://www.dgt.es> tramites and multas> tu coche> matriculación
The certificate of conformity (Certificado de Características) or proof of technical inspection (Tarjeta de Inspección Técnica) are only available after an actual inspection of the vehicle.
The addresses of the various technical inspections (ITV) at http://www.dgt.es/es/seguridad-vial/centros-colaboradores/itvs/
source : spain.diplomatie.belgium.be