Trailer Connections T7/T8 Models Only
If the vehicle has these trailer connections, they are located at the rear of
the cab for a tractor and at the rear of the chassis when towing a trailer. There
will be an air connection and an electrical connection.
Be sure that the couplings to the trailer are made correctly.
Air Connections
If the trailer air line connections will not be connected to another piece of
equipment, be sure to replace their protective caps.
Electrical Connections
This system is a seven-wire cable that will connect to the trailer, supplying
power to the trailer's lighting system. When not in use, it is stored
in the trailer air-hose storage bracket.
Heavy-Duty Trailer Wiring Package
The vehicle may have an eight-wire trailer towing harness. This harness, with
a seven-pin universal heavy-duty trailer connector, is attached to a bracket on the
platform hitch.
The Center High-Mounted Stoplamp (CHMSL) wire is tied next to the trailer wiring
harness for use with a trailer.
The eight-wire harness contains the following trailer circuits:
| • | Yellow: Left Stop/Turn Signal |
| • | Dark Green: Right Stop/Turn Signal |
| • | Light Green: Back-up Lamps |
| • | Dark Blue: Trailer Brake |
