Trailer Plugs and Sockets

There are a number of trailer plugs, with the flat connectors being the current standard.
The flat connectors come in 7 pin and the more recent 12 pin. The 12 pin connector has the 7 pins with an additional 5 heavy duty pins below.
Note that the 7 pin flat plug will connect with a 12 pin socket.

1 - Yellow - left hand turn                                             
2 - Black - reverse
3 - White - earth
4 - Green - right hand turn                                
5 - Blue - electric brakes
6 - Red - stop
7 - Brown - tail, clearance, side markers
8 - Orange - battery supply 12v                                   
9 - Pink - auxiliaries
10 - White - earth/gnu
11 - Grey - rear fog lamp                            
12 - Violet - auxiliaries

1 - Yellow - left hand turn                                             
2 - Black - reverse
3 - White - earth
4 - Green - right hand turn                                
5  Blue - electric brakes
6 - Red - stop
7 - Brown - tail, clearance, side markers