Parking Brake (With Air Brakes) - GMC TopKick 2007 Owner's Manual

Parking Brake (with Air Brakes)

Pulling it out applies the parking brake. The
parking brake light will come on when the air
parking brake is applied.
If your vehicle has air
brakes, you will have this
parking brake. It is
located above the radio
in the instrument panel.
Vehicles built for use as tractors or towing
vehicles have two air brake controls. They look
like this:
CAUTION:
{
When the yellow PARKING BRAKE and
the red TRAILER AIR SUPPLY knobs are
both pushed in, your rig will be free to
move. It could strike someone or
something. When both of these knobs are
pushed in, hold the regular brake pedal
down to keep your rig from moving.
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