Caravan/Trailer Wiring Connectors

camping out

One of the most confusing issues with camping can be the connection between your vehicle and the caravan/camper/trailer. There are a number of connector types for connecting your vehicle to the camping rig, and you can also source adapters to go from one to another. So here is a look at the most common varieties found (in Australia at least). This list should also offer a guide to adapting one connector type to another. The important thing is going to be point to point connectivity, eg stop light to stop light, brake to brake; and ensuring that the connector pin rating can handle the current demanded by the circuit.

Australian Standard 2513-1982 requires a minimum 7 pin connector, but some older types are still around and are included here for reference.

5 Pin Round Connector.

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This is an older type connector but obviously still found on older caravans. As you can see there is no allowance for auxiliary brake connections nor any other auxiliary services. If you have a need for other services then an upgrade is your best bet – preferably to a flat 12 pin.




6 Pin Round Connector.

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This again is an older type connector but in this case you get an extra pin for either your auxiliary braking circuit on the trailer, or some other service. If you do choose to use this connector for some other service make sure it is a relatively low current one. These pins are not rated for the likes of battery charging or 12 volt refrigerators.



7 Pin Round Connector.

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Another pin for your reversing lights. Actually there are two versions of this connector – large and small. The difference is pitch centre diameter – 20mm for the large and 13mm for the small. Pin 5 should be used for auxiliary brakes only to ensure interchangeability. It should be noted that 7 pin connectors are mandatory on all new trailer units registered after 1st Jan 1988. This ensures that all lighting and auxiliary brake requirements are met. Also important to note is that the pin connections and wire insulation colouring are now standardised to that shown.


7 Pin Flat Connector.

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Same pin-outs as for the round connector but the flat variety is considered more robust and less likely to be accidentally disconnected. This unit has a spring loaded cover that essentially locks the connector in place. Again it is recommended that you use pin 5 for auxiliary brakes. If you want more heavy current auxiliary connections then you need the big mother that follows.


12 Pin Flat Connector.

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This is basically the seven pin connector on steroids! An extra row of pins are larger than the others and thus can handle more current. There is an extra earth pin and I don’t really see how you can want more than this connector offers. You may not be able to find them down at your local hardware store, but hey, the Internet is a plentiful place! This is my preferred connector.


I hope you have found this post useful. If you have any comments to make, please do!


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