The answer to the missing dashes about the diagnosis of problems in a locomotive are respectively;
Mechanic
Electrician
When it comes to engines such as locomotives, there are two primary workers that work on it in the event of repairs and they are mechanics and electricians.
Mechanics are those who repair and maintain anything that has to do with the engine and mechanical parts of any type of engine while an electrician is the one concerned with diagnosis of electrical problems and responsible for carrying out any repairs required.
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