Mixer wagon electric controls

[O'Reilly]

Morning, when I operate any of the switches, nothing happens, and the stop lights come on the dash of the tractor, JD 6800. Current is getting to the machine. Presumably it's a short or something? Don't understand how it is affecting all three services . Any ideas?

 

[O'Reilly]

Just changed tractor, works on that one. Goodness knows what is wrong with the other one.

 

[Norfolk Hill Farmer]

No expert, the alternator, battery or earth could have a fault on the first tractor.