2002 Yamaha G19-AX "ULTIMA" (48V - DC MOTOR) Service and ...
The 48-volt cars form their own series, and this 2002 ULTIMA is one of them. It is listed as the G19-AX with model code G19EX, and Yamaha's service manual for it is LIT-19616-G1-90.
Coverage in that book runs from 1996 to 2002 and includes the earlier 48-volt cars: the G19-EP, G19-ER, G19-ES, G19-ET, G19-EU and G19-EW. Six companion models, one part number, because the platform carried through with few changes.
What a technician uses it for
Diagnosing the motor and controller with the factory's test points and expected readings, working through charging faults in order, tracing circuits on diagrams drawn as the harness was built, and reassembling chassis and brake components to Yamaha's torque values with the service limits that decide whether a part goes back on.
The plate is the final word on fitment, and here it reads G19EX.