The eligible trades for RRB JE:
Diploma in Computer Science, Computer Engineering, Civil Engineering, Mechanical, Production, Automobile, Electrical, Electronics, Instrumentation & Control Engineering, Tools & Machining, Tools & Die Making, or B.Sc in Civil Engineering from a Recognized University/Institute.
Now if you have a Diploma and then you have done BTech then you can apply for RRB JE. But if you have done only BTech in Automobile Engineering and don't have diploma in it then you aren't eligible for the course.
To know more about RRB JE visit the link below:
https://competition.careers360.com/articles/rrb-je-exam-pattern
I hope this answer helps. All the very best for your future endeavors!
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