With the many methods of towing in the RV world, you must have an electrical connection between the RV and the towed vehicle for lights, turn signals, brakes, etc..
Pre-made cables are available at most Camper part stores, as well as kits for wiring into the wiring harness of vehicles. And every smart RV owner learns what those wires do, and what the symptoms are when there is a bad connection.
RV Motorhomes will have either a 6-pin or 7-pin connector mounted somewhere near the Hitch for connecting to the towed vehicle..
Some of the wiring systems used for connecting a tow vehicle with a TOAD (or towed vehicle) are simpler than others, but there are standards for all of the connectors and how they are wired.
Here is a short overview of the most popular connector wiring standards:
a. 4-Pin Connector-
The most commonly used tow connector is the 4-pin connector.
The standard 4-pin connector is a flat plastic connector, with 3 pins either male or female, and the 4th pin the opposite sex.
The connector shown is for the wiring of the towing vehicle. The pins and their usage are;
PIN-1=Ground (male pin) White wire,
PIN-2=Tail Lights (and license plate light and side lights)= Brown Wire,
PIN-3=Left Turn & Stop Lights (Yellow Wire),
PIN-4=Right Turn & Stop Lights (Green wire).
b. 6-pin Connector
The standard 6-pin connector is a “Keyed” round metal connector with the following connections.
Those shown are from the wiring side of the towing vehicles connector. The Pins and their usage, are;
PIN-A (center pin = 12V (and is either red or Black),
PIN-TM -(at the guide) = Tail Lights (usually Brown wire),
PIN-GD =Ground (usually White),
PIN-LT=Left Turn Signal (usually Yellow),
PIN-RT=Right Turn (usually Green), and
PIN-S= Electric Brakes (usually Blue). This pin is used to provide a variable voltage to the electrical brakes of larger tow trailers and campers to assist in stopping them.
c. 7-Pin Connector-
The standard 7-pin connector is a “Keyed” round metal connector with the following connections. Those shown are from the wiring side of the towing vehicles connector. The pins and their usage, are;
PIN-1=Ground (usually White),
PIN-2=Electric Brakes (usually Blue),
PIN-3=Taillights (usually Green),
PIN-4=12V (usually Black),
PIN-5=Left Turn (usually Red),
PIN-6=Right Turn (usually Brown), and the
Center PIN= Auxiliary Power or Backup Lights (can be wired for either)
by Don Bobbitt, 2015
Copyright Don Bobbitt, 2015, All Rights Reserved
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