2004 Yamaha G23-EZ "UMAX MEDIUM DUTY I" (48V - DC MOTOR) ...
First-year electric UMAX cars, the 2004 G23-EZ among them, are covered by LIT-19616-G2-30. The code to verify is G23EZ and the drive is a 48-volt DC motor.
Coverage extends from 2004 to 2009 and nine variants, taking in both the carbureted and the electric G23 UMAX Medium Duty models. Yamaha kept them in one volume and noted the year differences in the text, which is worth knowing when you are checking whether a specification applies to an early car.
The book gives specifications and maintenance intervals, then battery and charging system work, solenoid and controller diagnosis with expected readings, motor service, rear axle and drive, brake adjustment, steering, front suspension, wheels, frame, body and complete wiring diagrams.
Quote the code and the part number together at the parts counter. On the UMAX line the naming varies but the code does not.