Trailer Wiring Information:
The following diagram conforms to the standard agreed upon by vehicle manufacturers and
companies producing the trailer connectors. This will
allow you to hook up your old trailer to a new truck, or bring home a new
commercially built trailer without any wiring hassles. The 7-blade connectors are the most widely used, and even if you donít need it now
Ė you will save yourself the hassle of upgrading at a later
date when you buy the next bigger and better trailer. (Backup lights
can be hooked up to 7. Auxiliary Yellow).
THIS VIEW IS LOOKING
AT THE TOW VEHICLE RECEPTACLE ON THE SCREW TERMINAL SIDE (the inside of the
socket where the wires attach).
(This is also
the view of the exterior trailer connector pins)
THIS VIEW IS LOOKING
AT THE TRAILER CONNECTOR PLUG ON THE SCREW TERMINAL SIDE (The inside of the plug
where the wires attach).
(This is also
the view of the pins when looking inside the cover of the tow vehicle
The following chart should be used as a general guide only, you should always
test before connecting your wiring.
This chart also may not be accurate for vehicles with factory installed
trailer harnesses. In past 2-3 years manufacturers have begun to match the wire
colors to the code for the common 7 way RV connector. More on that after the
Notes about GM OEM wiring harness. Most GM vehicles except '99 & 2000
Silverado's match the following.
your vehicle has a diagnostic indicator that tells you when a lamp is
burned out or not functioning, you may need special wiring adapters and
testers. Not using these adapters may cause damage to the vehicle wiring
|left turn & brake lights
||lt green w/orange stripe
|right turn & brake lights
||orange w/blue stripe
||black or black w/yellow stripe
|back up lights
||black w/pink stripe
|ground - see note 1
||black or grey
|In addition to the above some cars and trucks have a
separate light for the brake light, most commonly identified by amber
turn lenses in the rear. Chrysler and Jeep may have the separate light
and use red lenses. If you have this type of wiring a converter is
||lt blue or pink
||red w/green stripe
|Note 1: We recommend attaching the trailer harness
ground directly to the frame or a solidly attached sheet metal part,
using a screw or bolt. The single most common cause of trailer lighting
problems is a poor ground on the tow vehicle or trailer.
GM trailer wiring code
||12 volt +
|* Pickups only: since approximately 1996 the 12
volt + wire is orange. The orange and blue wires are in a separate
bundle taped to the wire harness that runs down the frame on the
drivers side. A white wire may also be found in that bundle, it is a
brake light wire which is not normally used for trailer wiring.
Dodge tow vehicles with the Factory Tow Package Brake
Connector Dodge vehicles with this package are equipped with a 15 amp fused
power line which is insufficient for 3 & 4 axle (6 or 8 brake) applications. For
3 & 4 axle (6 or 8 brake) applications a separate power wire should be installed
directly from the battery positive to the brake control and should include an
inline 30 amp auto reset circuit breaker.
Ford tow vehicles with the Factory Tow Package Brake Connector Ford vehicles
with this package are equipped with a 20 amp fused power line which is
insufficient for 3 & 4 axle (6 or 8 brake) applications. For 3 & 4 axle (6 or 8
brake) applications a separate power wire should be installed directly from the
battery positive to the brake control and should include an inline 30 amp auto
reset circuit breaker.