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Truck & Transport
Truck and Transport Mechanic Red Seal Certification
ABS, Stability Control, and Trailer Systems
Knowledge Check
ABS, Stability Control, and Trailer Systems
Knowledge Check
Knowledge Check
1 / 14
What is the function of the trailer hand valve (trolley valve) in a tractor-trailer combination?
A
To apply only the trailer service brakes independently for testing or maneuvering
B
To apply the trailer spring parking brakes
C
To control the trailer brake proportioning ratio
D
To supply air to the trailer reservoir from the tractor
Check Answer
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