2-33. PREPARATION FOR USE (Cont)
c. Connect Intervehicular Hoses.
This operation is performed at this
time to lock the brakes and prevent
movement of the semitrailer which
might damage the landing legs.
(1) Connect the two air hoses tagged SERVICE
and EMERGENCY on the towing vehicle,
on the semitrailer.
(2) Open the air lines shutoff valves on the
(3) If no air leakage is detected, apply the
brakes on the semitrailer from the towing
d. Completing Coupling Semitrailer to Towing Vehicle.
(1) Before the kingpin plate (3) starts to ride the
approach ramps (4), check that the kingpin
plate (3) is above the approach ramps (4).
Adjust the height as needed by using the
landing gear. Make sure the towing vehicle
fifth wheel coupler jaws (2) are open.
(2) Slowly back the towing vehicle until the
coupler jaws (2) engage the kingpin (1).
Visually check the coupling. You should
fifth wheel and the kingpin plate.
(3) Make sure the coupling is secure by inching the truck tractor forward. If the coupling is not locked,
rock the truck tractor back and forth sIowly until the kingpin (1) is locked in the fifth wheel (5).
(4) Connect intervehicular cables. Check lights. Connect each intervehicular cable by opening the
cover on the plug of the intervehicular cable. Lift the spring loaded cover of the 12-volt or 24-volt
receptacle, whichever is applicable on the front of the semitrailer. Aline slot on plug with alining
key of receptacle. Release cover. Operate lights from the towing vehicle to make certail all are in