Chase nails his In-cab Brake Tests

Per Michigan CDL Manual:
"Failure to perform all three components of the air brake
check correctly will result in an automatic failure of the
vehicle inspection test. Air brake safety devices vary.
However, this procedure is designed to see that any safety
device operates correctly as air pressure drops from
normal to a low air condition. For safety purposes, in areas
where an incline is present, you will use wheel chocks
during the air brake check. The proper procedures for
inspecting the air brake system are as follows:
✓ With the air pressure built up to governor cutoff (120 -
140 psi), ✓ shut off the engine leaving the key in the
“on” or “battery charge” position, chock your wheels if
necessary, ✓ release the parking brake (all vehicles),
and the tractor protection valve (combination vehicle)
and ✓ fully apply the foot brake. ✓ Hold the foot brake for
one minute. Check the air gauge to see if the air
pressure drops more than three pounds in one minute
(single vehicle) or four pounds in one minute
(combination vehicle).
Warning Devices
✓ Begin fanning off the air pressure by rapidly applying
and releasing the foot brake. Low air warning devices
(buzzer, light, flag) should activate before air pressure
drops below 55 psi or level specified by the
manufacturer.
Pop-Off
✓ Continue to fan off the air pressure. At approximately
40 psi on a tractor-trailer combination vehicle (or level
specified by the manufacturer), the tractor protection
valve and parking brake valve should close (pop out).
On other combination vehicle types and single vehicle
types, the parking brake valve should close (pop out)."
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