With the Florida CDL Driver Handbook, you have the right to study up on the concerns that specifically relate to earning her CDL endorsement.

You are watching: How can you test that air flows to all trailers


Table the Contents

6. Combination Vehicles

Use the seven-step inspection procedure explained in section 2 to examine your combination vehicle. Over there are more things to inspect on a mix vehicle than on a solitary vehicle. (For example, tires, wheels, lights, reflectors, etc.) However, there are also some brand-new things to check. These are discussed below.

6.5.1 - added Things to examine During a Walkaround Inspection

Do this checks in enhancement to those already detailed in ar 2.

Coupling system Areas


*
Figure 6-8
inspect fifth wheel (lower). Securely an installed to frame. No lacking or damaged parts. Sufficient grease. No visible an are between upper and lower fifth wheel. Locking jaws about the shank, not the head that kingpin. See number 6.8. Relax arm correctly seated and also safety latch/lock engaged. inspect fifth wheel (upper). Glide bowl securely an installed to trailer frame. Kingpin not damaged. Air and also electric lines to trailer. electric cord steady plugged in and secured. Wait lines properly connected to glad hands, no wait leaks, correctly secured with enough slack for turns. All lines complimentary from damage. Sliding fifth wheel. Slide not damaged or parts missing. Appropriately greased. Every locking pins present and also locked in place. If air powered--no wait leaks. Check that 5th wheel is not so far forward the tractor frame will struggle landing gear, or the cab struggle the trailer, throughout turns.

Landing Gear

completely raised, no absent parts, not bent or otherwise damaged. Crank take care of in place and secured. If strength operated, no wait or hydraulic leaks.

6.5.2 - combination Vehicle Brake Check

Do these checks in enhancement to section 5.3: Inspecting air Brake Systems.

The adhering to section defines how to inspect air brakes on mix vehicles. Inspect the brakes on a twin or triple trailer together you would certainly any mix vehicle.

Check the Air operation to every Trailers. use the tractor parking brake and/or chock the wheel to host the vehicle. Wait because that air press to reach normal, then press in the red "trailer wait supply" knob. This will certainly supply air come the emergency (supply) lines. Use the trailer handbrake to provide air come the business line. Go to the rear of the rig. Open the emergency line shut-off valve in ~ the behind of the last trailer. You must hear air escaping, reflecting the entire system is charged. Close the emergency line valve. Open the service line valve to inspect that business pressure goes with all the trailers (this check assumes the the trailer handbrake or the organization brake pedal is on), and also then nearby the valve. If you execute NOT hear air escaping from both lines, examine that the shut-off valves top top the trailer(s) and dolly(ies) are in the open up position. You MUST have actually air every the way to the earlier for every the brakes to work.

Test Tractor security Valve. Charge the trailer air brake system. (That is, build up typical air pressure and push the "air supply" knob in.) closeup of the door the engine off. Step on and also off the brake pedal numerous times to alleviate the air push in the tanks. The trailer wait supply manage (also called the tractor security valve control) have to pop out (or walk from "normal" come "emergency" position) as soon as the wait pressure falls into the pressure range specified by the manufacturer. (Usually within the selection of 20 to 45 psi.)

If the tractor protection valve doesn"t work-related right, one air water tap or trailer brake leak could drain all the wait from the tractor. This would cause the emergency brakes to come on, with possible loss the control.

Test Trailer Emergency Brakes. Charge the trailer wait brake system and also check the the trailer rolls freely. Then stop and also pull the end the trailer wait supply control (also called tractor defense valve regulate or trailer emergency valve), or place it in the "emergency" position. Traction gently top top the trailer through the tractor to inspect that the trailer emergency brakes are on.

Test Trailer service Brakes.

See more: How Are The Equator And Prime Meridian Alike, What Are The Equator And The Prime Meridian

Check for normal air pressure, relax the parking brakes, relocate the vehicle forward slowly, and apply trailer brakes v the hand manage (trolley valve), if so equipped. You need to feel the brakes come on. This speak you the trailer brakes are connected and also working. (The trailer brakes must be tested v the hand valve but controlled in normal operation with the foot pedal, which applies air to the company brakes at all wheels.)


Subsection 6.5Test her Knowledge

i beg your pardon shut-off valves should be open and which closed? How can you test that air operation to all trailers? How deserve to you test the tractor protection valve? How deserve to you test the trailer emergency brakes? How can you test the trailer business brakes?

These questions might be on your test. If you can"t answer all of them, re-read subsection 6.5.