Automotive service technicians inspect, maintain, and repair automobiles and light trucks. Mechanics perform basic care maintenance, such as oil changes and tire rotations, diagnose more complex problems, and plan and execute vehicle repairs. Certification and advancement. National Institute for Automotive Service Excellence (ASE) certification has become a standard credential for automotive service technicians. Certification is available in eight different areas of automotive service, such as electrical systems, engine repair, brake systems, suspension and steering, and heating and air-conditioning.