Ford F-650 Owner's Manual page 123

TRAILER BRAKE HAND CONTROL (IF EQUIPPED)
The hand control, located on the
right-hand side of the instrument
panel, is used to apply the trailer
service brakes which are
independent of the truck or tractor
service brakes.
WARNING: The hand control should never be used to apply the
brakes when the tractor and trailer are parked unattended. Air
may leak from the system and the vehicle could possibly move,
resulting in possible property damage, personal injury or death.
The hand control operates a valve that provides gradual control of air
pressure applied; when the valve is only partially applied, the trailer
brakes can be overridden by pressing fully on the brake pedal.
To apply the trailer brakes using the hand control, move the lever
downward. The further the lever is pushed down, the greater the air
pressure is applied to the brakes. The lever remains in place until
manually moved.
To release the trailer brakes, move the lever up completely.
TRAILER AIR SUPPLY AND PARKING BRAKE MODULAR
CONTROLS (IF EQUIPPED)
The trailer air supply valve delivers
air to the trailer supply and
automatically pops out, shutting off
the trailer supply, if pressure is
decreased to approximately 35 psi
(249 kPa).
The parking brake controls the
spring brakes on the tractor. When
the knob is pulled out it causes the
trailer supply valve to pop out,
applying both the tractor and trailer
parking brakes. The trailer brakes
may be independently released by pushing only the trailer air supply
valve in.
2012 F-650/750 (f67)
Supplement, 2nd Printing
USA (fus)
Driving
TO
TRAILER
AIR SUPPLY
NOT FOR PARKING
TO
123