Ford 2013 F-650 Owner's Manual page 161

160
Parking Brake Light Illumination Due to Low Air Pressure
If at any time during vehicle operation air pressure becomes too low, the
parking brake may apply and the parking brake light turns on.
If the parking brake is applied due to low air pressure, immediate service
is required to the parking brake system.
Parking Brake Warning System
If the parking brake light blinks and a chime sounds when pulling the
yellow control knob out, this indicates the parking brake is not
functioning properly. Seek service for the parking brake immediately.
With the ignition key not in the run position:
• A chime sounds if the parking brake remains released (or in an
unknown state). The chime stops in approximately eight minutes or
until the parking brake is applied. Seek service for the parking brake
immediately.
Diesel engines: Parking brake light operation (the light only works
when the ignition key is in the run position):
• On: Parking brake applied.
• Off: Parking brake released and no faults or malfunctions.
• Blink and chime: Parking brake released (or in an unknown state)
and faults or malfunctions exist.
Releasing Spring Manually
WARNING: Do not attempt to disassemble the parking brake
chamber under any circumstances. The high spring load may
cause serious injury.
WARNING: Block the wheels to help prevent the vehicle from
moving.
WARNING: Unexpected and possibly sudden vehicle movement
may occur if these precautions are not taken.
If hydraulic pressure is released from the spring brake chamber the
power spring applies the brake and, unless hydraulic pressure can be
re-established, the spring brake must be released as follows in order to
move the vehicle.
2013 F-650/750 (f67)
Owners Guide gf, 2nd Printing, March 2013
USA (fus)
Brakes