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After a few minutes, the trailer system should be fully
charged. When it is, the air pressure gage will show
about 125 to 135 psi (862 to 931 kPa).
For driving with a trailer, the yellow and red (if equipped)
knobs must be pushed in. It’s the same when you’re
not pulling a trailer except that the red trailer air supply
knob must be pulled out.
{CAUTION:
If you apply any one of the air brake parking
controls while the vehicle is moving, your rig
will stop suddenly. If you are not ready for
this, you or others could be injured. Don’t
apply any one of these controls while you’re
driving, unless you have to make an
emergency stop.
If the air pressure drops below 60 to 70 psi
(413 to 482 kPa), the primary brake light and warning
buzzer will come on. If the air pressure drops to
35 to 45 psi (241 to 310 kPa), the red trailer air supply
knob will automatically pop out and apply the spring
brakes on the trailer.If the air pressure drops to 35 to 45 psi (241 to 310 kPa),
the yellow park brake knob will automatically pop out
and apply the spring brakes on the truck or tractor.
If you ever have a complete loss of air so that your air
brakes automatically apply, there is a way that the
tow operator can release the parking brakes to tow the
vehicle. SeeTowing Your Vehicle on page 4-31.
{CAUTION:
If your vehicle is left in gear, the engine can
start if the vehicle starts to roll. This can easily
happen if you have the diesel engine. Shift the
transmission into NEUTRAL (N) before you
leave the vehicle.
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Parking Over Things That Burn
{CAUTION:
Things that can burn could touch hot exhaust
parts under your vehicle and ignite. Do not
park over papers, leaves, dry grass or other
things that can burn.
Engine Exhaust
{CAUTION:
Engine exhaust can kill. It contains the gas
carbon monoxide (CO), which you can not see
or smell. It can cause unconsciousness and
death.
You might have exhaust coming in if:
Your exhaust system sounds strange or
different.
Your vehicle gets rusty underneath.
Your vehicle was damaged in a collision.
Your vehicle was damaged when driving
over high points on the road or over road
debris.
Repairs were not done correctly.
Your vehicle or exhaust system had been
modi ed improperly.
If you ever suspect exhaust is coming into
your vehicle:
Drive it only with all the windows down to
blow out any CO; and
Have your vehicle xed immediately.
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Running Your Engine While You
Are Parked
It is better not to park with the engine running. But if
you ever have to, here are some things to know.
{CAUTION:
Idling the engine with the climate control
system off could allow dangerous exhaust into
your vehicle. See the earlier Caution under
Engine Exhaust on page 2-37.
Also, idling in a closed-in place can let deadly
carbon monoxide (CO) into your vehicle even if
the climate control fan is at the highest setting.
One place this can happen is a garage.
Exhaust — with CO — can come in easily.
NEVER park in a garage with the engine
running.
Another closed-in place can be a blizzard. See
Winter Driving on page 4-25.
{CAUTION:
It can be dangerous to get out of your vehicle
if the shift lever is not fully in PARK (P) with
the parking brake rmly set. Your vehicle can
roll. Do not leave your vehicle when the engine
is running unless you have to. If you have left
the engine running, the vehicle can move
suddenly. You or others could be injured. To
be sure your vehicle will not move, even when
you are on fairly level ground, always set your
parking brake and move the shift lever to
PARK (P).
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