In the world of heavy-duty truck diagnostics and repair, few software suites are as revered—and as misunderstood—as . Developed by Volvo Trucks, PETKA (Parts and Service Electronic Catalog) is an indispensable tool for mechanics, fleet managers, and parts specialists. It provides detailed electronic parts catalogs, service bulletins, wiring diagrams, and hydraulic schematics for Volvo trucks, buses, construction equipment (Volvo CE), and even Renault trucks.