If a trailer's spring brakes do not release when you push the tractor air supply control, you should:

Question

It is important that all of your vehicle's equipment is in proper working condition before you begin a trip. If a trailer's spring brakes do not release when you push in the tractor air supply control, you should make sure the air line connections are properly attached and sealed.

Accepted Answer

Check the air line connections.

Answer

Release the pintle hook.

Answer

Replace the spring brakes.

Answer

Drive normally without checking anything.