This manual covers YANMAR TNV Series internal combustion engines, specifically focusing on their electrical control systems and service tool operation. The TNV Series encompasses a range of EPA TIER3 compliant models including the 3TNV84T-Z, 4TNV84T-Z, 4TNV98T-Z, 4TNV98-Z(R80-7A), and 4TNV98-E(R55-7A, R55W-7A), as well as OPTION models such as the 3TNV82A-Z, 3TNV88-Z, 3TNV88-E, and 4TNV88-E. These engines are designed for applications requiring precise electrical control and reliable service. The purpose of this Electrical Control Manual and Service Tool Operation Manual is to provide comprehensive guidance for users of all levels, from first-time owners to professional technicians. It details general information, electrical control procedures, and the operation of service tools, all presented in an easy-to-read format. By following the information provided, users can effectively maintain their YANMAR TNV Series engines, prevent premature failures, and reduce unnecessary repair costs, thereby saving time and money.