Trailer Tow - Wiring Information

NO: 08-33-96

GROUP: Electrical

DATE: Oct. 11, 1996

SUBJECT:
Trailer Tow Wiring Information

MODELS:
1994 - 1997 (BR) Ram Truck

DISCUSSION:

Chrysler Corporation has offered optional trailer tow packages on all 1994 through 1997 Dodge Ram Trucks and has made trailer tow packages available through Mopar for vehicles that were not built with the trailer tow package. Several changes to the trailer tow wiring have occurred since the Dodge Ram Truck was introduced. This bulletin identifies these changes and provides part numbers for the trailer tow wiring harnesses, relays, and flashers. In addition, this bulletin identifies the part numbers for the Mopar trailer tow packages required to adapt trailer wiring to a vehicle that did not have the trailer tow package installed as original equipment from the factory.

TRAILER WIRING IDENTIFICATION





The trailer tow wiring 7-terminal connector (located on the receiver hitch), is configured with the circuits as shown.

Some of the circuits of the 7-terminal connector may be somewhat difficult to identify. The following explains those circuits that may be somewhat confusing.

Cavity-2 Trailer Tow Electrical Brake Output

This circuit provides a connection between the trailer tow 7-terminal connector and an electric trailer brake system. An electric trailer brake kit was introduced at the beginning of the 1996 model year. The kit includes an electric trailer brake jumper with unterminated leads, heavy duty flasher, a 7-terminal to 4-terminal adapter, and an instruction card. The instruction card identifies that the trailer brake circuit mating connector is located in the instrument panel near the steering column. This kit is utilized throughout Chrysler Corporation on several different vehicle applications and on the Dodge Ram truck, the mating connector can be located behind the fuse block near the dash panel, not near the steering column as stated by the instruction card.

Cavity-3 Trailer Tow Relay

The trailer tow relay circuit provides a 30 amp circuit (40 amp for 1996 and 1997) to feed the trailer's tail/park lamp circuit. This circuit is connected to fuse 7 in the Power Distribution Center (PDC). The relay is also located inside the PDC. The relay is energized anytime the park lamp switch is turned ON. The park lamp switch provides the necessary current to operate the trailer tow relay coil.

WARNING:
IT IS IMPERATIVE THAT THE TRAILER TOW RELAY BE UTILIZED WHEN OPERATING THE TAIL/PARK LAMPS ON THE TRAILER. THE CURRENT CARRYING CAPACITY OF THE HEADLAMP SWITCH IS LIMITED TO THE LAMPS UTILIZED BY THE VEHICLE ONLY.

Cavity-4 Fused B+

This circuit provides a 30 amp (40 amp for 1996 and 1997) circuit for operating electrical circuits on the trailer. This circuit is connected to fuse 7 in the PDC. This circuit does not contain any isolation device between the 7-terminal connector and the fuse. Current will not be interrupted to this circuit with the ignition switch in the OFF position.

Cavity-1, Cavity-5, Cavity-6, and Cavity-7 are self explanatory.

MOPAR TRAILER TOW PACKAGE

If the Ram Truck does not have the trailer tow package installed at the factory, the truck wiring can be converted so that trailer wiring can be connected to the truck's wiring system. The following trailer tow wiring harnesses are available from Mopar.

82401264 4-Terminal Trailer Tow Wiring Package

82400961 7-Terminal Trailer Tow Wiring Package (1994 All Models and 1994 - 1997
Cab Chassis)

82401265 7-Terminal Trailer Tow Wiring Package (1995 - 1997 Models except Cab
Chassis)

NOTE:
THE 4-TERMINAL TRAILER TOW WIRING PACKAGE SHOULD NOT BE USED WITH TRAILERS THAT HAVE ADDITIONAL RUNNING LIGHTS OTHER THAN THE REAR TAIL/PARK LAMPS.

For additional information regarding Mopar's trailer tow packages, refer to the 1996 Mopar Accessories P.A.D. Application Guide & Price List.

TRAILER TOW PACKAGE COMPONENTS AND ACCESSORIES

The following components and accessories can be ordered through Mopar to aid in trailer wiring connections.

82400554 7-terminal trailer wiring connector
82401217 7-terminal to 6-terminal adapter
56019823 7-terminal to 4-terminal adapter
04608650 Trailer Tow Relay (1994-1996)
04638094 Trailer Tow Relay (1997)
02932877 Heavy Duty Flasher

POLICY: Information Only