(3) Connect the brake hoses in the proper order.
(4) Open the cutout valves, if so equipped, or
actuate the trailer charge valve to allow pressure to
build up in the reserve tank on the trailer.
(5) Apply pressure to the trailer brakes, using hand
valve, if they are operated independently. If the trailer
brakes are not operated independently, proceed as
(a) For vacuum operated brakes, turn off the
service line valve and disconnect the hose; this should
automatically apply pressure to the trailer brakes.
( b ) For air operated brakes, turn off the
emergency line valve, if so equipped, and disconnect the
hose; this should automatically apply pressure to the
(6) Back the tractor under the trailer until the
fifth wheel engages the trailer king pin and locks. If
the tractor is not in line to engage the trailer king pin
and must be repositioned, uncouple the air hose before
moving the tractor to avoid breaking the hose.
(7) When the fifth wheel and the king pin are
l o c k e d , test security of the hookup. Remove the
chocks, and place the tractor in first gear; engage the
clutch; and move the tractor forward slightly while
applying pressure to the trailer brakes.
(8) If the trailer is properly connected, stop the
tractor and set the parking brake; double check all
couplings, reconnect the brake air hose, and open the
air valve, if so equipped.