The unit has only PARK, REVERS AND NETUTRAL indicator lights is that not correct?
what light are on at the same time?
The gear position switch could be bad or shorted wiring problem. The gear position switch is on the left rear of the motor, disconnect the switch and test ride the unit to see if the lights L, H,N,R come on.
let me know what the results are.
IT IS PART #2