System Parts第 19 / 60 题
Why should the trailer hand valve NOT be used for parking?
a.Air could leak out and release the trailer brakes
b.It applies too much braking force to the tractor
c.It drains the primary air tank
d.It disables the low-pressure warning
解析
You should not use the trailer hand valve for parking because the air could leak out and release the trailer brakes over time. The spring-loaded parking brakes should be used instead, since they are held on by springs and do not depend on air pressure. Relying on the hand valve could let the trailer roll.
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