the more info we have the better we can help you, as Bert stated faulty switch and or wiring.
give us the model number, it should be located under the seat. it will not be on the hood :laughing:
most likely a seat switch.
I had a similar issue with my 2165. It would start, but then quit.
After a great deal of testing, I replaced the Voltage Sensor PN 925-3251, and it's worked fine since. Apparently, if something goes wrong with that, it will start, but then quit.
It's also possible that the brake safety switch is either disconnected, or the switch has died. It's in a very difficult to reach place underneath the steering column.