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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
decreases 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.
Initial Charge
With the air system completely discharged, both knobs (A and B) are
out. When the air pressure reaches 70 psi (483 kPa), the trailer air
supply (A – red knob) may be pushed in and should stay in, charging the
trailer air system and releasing the trailer brakes.
B
A
B
A
154
Brakes
2013 F-650/750
(f67)
Owners Guide gf, 2nd Printing, March 2013
USA
(fus)