Air Connections; Electrical Connections - GMC C series 2002 Owner's Manual

Trailer Connections (If Equipped)
If your vehicle has these connections, they are located at
the rear of the cab. There is an air connection and a
trailer electrical connection.
Be sure that the couplings to the trailer are
made correctly.

Air Connections

The red line is the supply
line. It provides emergency
or constant air pressure. The
blue line is the control line,
providing service air.

Electrical Connections

-
This system has a seven wire cable that will go to the
trailer to supply electrical power to the trailer's lighting
system. When not in use, it is stored in the trailer
-
air hose storage bracket.
NOTICE:
Starting in 1998, the center pin (also known as
the auxiliary circuit) of the seven
electrical connector will be wired to provide
continuous power for the trailer anti
systems when the ignition key is in ON. Care
should be taken to insure that continuous power
on this circuit will not cause damage to the trailer
electrical system.
Consult with the trailer manufacturer for the
proper operation and checking procedures for
-
the trailer anti lock brake systems.
-
pin trailer
-
lock brake
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