I need help please, In Aus. The wiring for a trailer or caravan is different as you probably know. I just bought a,2004 L322 and i need electric brakes for the caravan, this is where it got tricky, i managed to run all the wiring for the controller except the blue line to pin 5, now when i checked the plug it was wired to Aus standard except there was a blue line in pin 5 from the ECU, so i had black in pin 2 , brown in pin 7 and the blue in pin 5. To allow pin 2 to be used for power to the caravan fridge i cut and spliced the black onto the brown to make a single connection into pin 7, i also cut the blue line coming from the ECU and joined the blue from the brake controller making pin 5 the brake line, all good i thought. brake lights work, indicators work, reverse lights work but no running lights, instead when i switch on the light switch i get a terrible stattic type sound coming from the back on the side where the GPS disc player is???

So i undid all my connections and returned the wiring to how i found it, someone suggested i disconnect the battery for a while, i did that alsol no luck, no lights, just that horrible stattic. Please help

I managed to find where that static noise wascoming from, the speaker in the lefthand rear door and wheni turn on the light switch the gong sounds twice and the control panel comes on.

well i am very happy to apologise to everyone, i have been scratching my bald head till it bleeds and now it turns out that the problem wasn,t with my connections at all, it seems there is a fault with the dash lights dimmer switch,but what that has to do with the speaker stattic is another thing for another day

Hi mate, glad you sorted it. Potentiometers (the dimmer is most likely one) have a habit of causing irratic voltage fluctuations when failing, those are probably responsible for the static you heard on the speaker as the electromagnetic radiation of the fluctuations are picked up by the speaker. So hopefully the dimmer replacement sorts out the static too . MY 2010 5.0 SC Galway green and sand interior!!
Have the Faultmate MSV2 Extreme to be tinkering with the settings etc. !!

I don't know if this will help at all but, i had a customer drop in an 03 FF with terrible interference through the speakers when the lights were on and the engine was running!

Turned out the ambient LED door lighting plug is the same as the speaker plug in the early models! So, lights on & engine running put 12v back through the audio system speaker wiring causing the noise!