Electrical wiring - An important aspect of selecting your trailer hitch

 

In order to "legally" tow a trailer, proper wiring must be installed between your vehicle and your trailer to provide functional rear lights, turn signals and braking lights on the trailer.

 

Several types of electrical wiring are available to answer various towing requirements.

 

4-pin wiring with flat plug

4-pin wiring with flat plug

The 4-pin wiring with flat plug (connector) fulfill basic requirements including three lighting functions:

  • Right turn signal and brake light (green wire)
  • Left turn signal and brake light (yellow wire)
  • Taill lights, license plate and side marquer (brown wire)
  • Ground wire (white wire)

 

5-pin wiring with flat plug

Câblage à 5 brins avec fiche plate


The 5-pin wire with flat plug (connector) is equivalent to the 4-pin wiring but with an extra blue that can be connected to the trailer brake or an auxiliary source of power. This wiring is often used for trailer tents, utility trailers or boat trailers.

  • Right turn signal and brake light (green wire)
  • Left turn signal and brake light (yellow wire)
  • Taill lights, license plate and side marquer (brown wire)
  • Ground wire (white wire)
  • Trailer brake or auxiliary power source (blue wire)

 

6-pin wiring with rectangular plug

6-pin wiring with rectangular plug


This 6-pin wiring with a rectangular plug (connector) - that measures 3/4" by 1" - is often used for small motorcycle or smowmobile trailers or utility trailers.

  • Right turn signal (green wire)
  • Left turn signal (yellow wire)
  • Tail lights (brown wire)
  • Ground wire (white wire)
  • Trailer brake and auxiliary source of power (red and blue wire)

 

6-pin wiring with round plug

6-pin wiring with round plug


The 6-pin wiring with a 1" diameter round plug (connector) includes one or two extra wires for lighting functions such as back up lights, brake control or a 12 volts auxiliary source of power. This wiring is adequate for horse, landscaping and car trailers.

7-pin wiring with round plug

7-pin wiring with round plug


This 7-pin wiring with a 2" diameter round plug (connector) is the most popular for heavy load towing. It  contains an extra wire for back up lights or an auxiliary source of power. This wiring is used for large capacity trailers (landscaping, construction, cars, boats, horses, etc.).