InspectionQuestion 30 of 60
How can you test whether the trailer emergency brakes work during an inspection?
a.By revving the engine in neutral
b.By charging the trailer air, shutting off the tractor engine, then pulling the trailer air supply valve out and checking the trailer brakes apply
c.By bouncing the trailer
d.By disconnecting the light cord
Explanation
To test the trailer emergency (spring) brakes, charge the air system, then pull out the trailer air supply valve (or let air bleed) and confirm the trailer spring brakes set. You can then apply the tractor gently in low gear to confirm the trailer stays put. This verifies the emergency braking function before driving.
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