This service repair manual provides comprehensive information for the Hyundai 15L/18L/20L-7A and 15L(G)/18L(G)/20L(G)-7A Forklift Truck series. These models, designed for compact to medium-duty material handling, are engineered for reliability and efficiency in warehousing, manufacturing, and distribution environments. The manual covers a range of lift capacities, typically from approximately 1.5 to 2.0 tons, and is intended to support the operational longevity and performance of these industrial vehicles. This manual is designed to be an exhaustive resource for Do-It-Yourselfers, maintenance technicians, and repair shops. It details the structure, function, removal, installation, disassembly, assembly, and troubleshooting of all major systems, including the general unit, power train, brake system, steering system, hydraulic system, electrical system, and mast. With detailed schematics, wiring diagrams, and diagnostic information, this manual empowers users to perform accurate servicing, adjustments, and repairs, ensuring the safe and effective operation of their Hyundai forklift.