Ok - a bit of an update re: the trailer brakes....
Connected the camper up tonight and got some not so good results 
At first connect up the D4 threw up every conceivable error which included transmission fault, EBD failure etc etc! I disconnected the trailer plug and after two re-starts of the D4 everything cleared.
I then swapped pin number 2 and 5 over forgetting that 1 and 5 had been swapped by the sparky  Basically this made the brake controller show that brakes applied constantly even when the brake pedal wasn't depressed.
 Basically this made the brake controller show that brakes applied constantly even when the brake pedal wasn't depressed. 
Again I disconnected the trailer electrics which caused the controller to appear to operate normally with the red indicator light only coming on with the brakes. I did notice however that when the trailer electrics were connected with the ignition off the green light did indicate to show trailer brakes present however as soon as the ignition was cycled it went solid red. I also noticed that with the when the ignition was off and I closed the drivers door the brake lights flashed!
Ran out of light and time at this point - trailer adapter plug re-wired (KT762) as follows, will see how that goes: 
 1  left hand turn -  yellow                                       
  2  reverse  -  black                                                                        
  3earth  -   white
  4   right hand turn  -   green
  5    electric brakes  -  blue  
 6  stop  -  red
 7   tail, clearance, side markers  -  brown
Need to also add some traditional lights to the camper to get the D4 to recognise its there!
Cheers Phil
				
			
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