Ford F-650 2011 Supplement Manual page 120

Driving
Parking brake control (knob)
Pull the yellow parking brake knob
out to apply the parking brake. Push
the knob in to release the parking
brake.
WARNING: This control is
used for parking only. Do
not leave the vehicle unattended
after setting the parking brake
without placing the transmission
in R (Reverse) for manual
transmission, N (Neutral) for
automatic transmission (except
Allison 2200 transmission) or P
(Park) (Allison 2200
transmission). Use of wheel
chocks is also recommended in
hilly or off-road usage.
The parking BRAKE warning light in
the instrument cluster illuminates
and remains illuminated (when the
ignition is turned to the on position)
until the parking brake is released.
Releasing spring brake with air pressure
The air system in all vehicles with spring-actuated rear wheel parking
brakes is equipped with a tank valve located on the supply or service air
tank for connection to an outside air supply. The valve permits the
system to be recharged with air from an outside source, releasing the
spring-actuated parking brakes. The vehicle may then be towed in an
emergency.
An outside air source can be used only if the protected system is in
operating condition. If air pressure cannot be restored in the protected
air system, the spring-actuated brakes must be released manually.
120
2011 F-650/750 (f67)
Supplement, 2nd Printing
USA (fus)
P