Theseplugs can still be found on older trailers and boat/horse trailers. 13-pole plugs are used with caravans and more modern objects. A caravan always has a 13-pole connection. Wiring diagram for 7-pin connector. Direction indicator left | yellow; Rear fog lamp | blue/brown; Mass (for contacts 1 to 7) | white; Direction indicator right | green XAUTOHAUX 5ft 7 Way Round to 5 Way Pin Flat Trailer Wire Coiled Wiring Connector Adapter Plug for Truck RV Trailer Full Length 5 Foot (60 Inches) 167. 50+ bought in past month. Save 7%. $1999. Typical: $21.49. Lowest price in 30 days. FREE delivery Thu, Oct 26 on $35 of items shipped by Amazon. needsboth 12N and 12S 7-pin sockets, but with modified 12S wiring. See Section 3.3. Caravan built since 1 September 2008, and some Continental caravans, particularly if privately imported, or commercially imported in small numbers only - Towcar needs a single 13-pin socket. See Section 3.4. An Traileradapter converts a tow vehicle's 7-pole wiring connection to a 5-pin Delphi connection and a 2-pin camera connection for towing trailers with a backup camera. Coiled cord for extra flexibility. ProPlus343543 Trailer Lighting Testing Device 13 Pin 12 V Socket 12 V Diagnostic Tester for Caravan, Trailer, Tail Brake Car Light, Lorry Towing Vehicle Rear Indicator, Brake Light Tester / Testing Gauge with LED Display. 40. £2549. FREE delivery by Thursday 3 Aug. Only 3 left in stock. 7Pin (AS 4735) for Heavy Duty Vehicles. This connector is based on both SAE J560 and ISO 1185 and is providing either 12V, 7 x 40A or 24V, 7 x 20A. The voltage varies from vehicle to vehicle. Pin 1 - White - Earth. Pin 2 - Black - Left hand rear , clearance and marker. Pin 3 - Yellow - Left hand turn. The7 pin round trailer wiring diagram shows a connection between the trailer plug and the trailer wiring. This diagram usually comes with the trailer. It is the most common type of connection used for trailers. The diagram shows the color-coded wires that are used to connect the trailer plug to the trailer wiring. BEIJISTAR7 Pin to 13 Pin and 13 Pin to 7 Pin Towing Adapter, Trailer Plug Socket Adapter, 12V Waterproof Electric Adapter Plug Socket Converter Connector, for Caravan RV Boat Cars Truck Trailer. 4.5 (95) £999. Save 5% Pin2 is blue, and is for the fog light on trailer/light board. Pin 3 is White - earth. Pin 4 is Green and is the right Indicator. Pin 5 is Brown - Right tail/side light. Pin 6 is Red, Brake/Stop light. Pin 7 is Black, Left tail/Side light. This matches up with the wiring i have on the genuine honda harness: 7Pin Trailer Plugs. Next up is the seven pin trailer plug, which comes in flat or round. In the round, you can get a big size, or a small size. Usually the big is used on trucks or heavy machinery. These vehicles have a lot more lights and require more power to be fed through the plug. AlfOiH.