Trailer Plug wiring 7 pin
7 Pin Round Plug and Socket
There is a large and small variety of this plug and socket type. Type 1 is the large 7 pin connector type with a PCD (Pitch Centre Diameter) of 20mm, whilst Type 2 is the small 7 pin connector type with a PCD of 13mm. Both Type 1 and 2 plugs have a locating notch at the bottom.
(For reference - a Type 3 connector is the flat variety and this comes in 7 pin and 12 pin.)
Please note that because of interchangeability problems that may arise, it is recommended that pin number 5 in the 7 pin connectors be used only for service brakes. If auxiliary circuits are required, then the 12 pin Type 3 connector would be preferable.
7 pin connectors are mandatory on all new trailer units first registered after January 1, 1988, allowing sufficient connections to cope with all lighting requirements and electric brake controls. Since the introduction of the mandatory 7 pin connector, all wiring connections have been standardised and the use of a seven wire cable and standardised colouring has also been adopted. The 7 pin round Type 1 and Type 2 connectors are found in all states and territories throughout Australia.
o Pin 1 - Yellow - Left-hand turn indicator
o Pin 2 - Black - Reversing signal
o Pin 3 - White - Earth return
o Pin 4 - Green - Right-hand turn indicator
o Pin 5 - Blue - Service brakes
o Pin 6 - Red - Stop lamps
o Pin 7 - Brown - Rear lamps, clearance and side marker lamps
Submitted by Ian Johnson @October 2014
