Practice question

What is the correct order to disconnect the air lines and electrical cord when uncoupling?

  1. Leave them on the trailer; the next driver will move them
  2. Disconnect first, then secure them on dummy couplers or hangers
  3. Cut them with a knife if they are stuck
  4. Disconnect only the red line

Answer: B — Disconnect first, then secure them on dummy couplers or hangers

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