Ok...need some help here...Towing the Mustang next week to a racing event, and Germans use a 7-11 pin trailer connection...Mine only has the 4 pin flat pigtail. I already have a 7 pin connector that I was planning on using (with an adapter in case the trailer I rent has the 11 pin) Looking on line I found that 1 is left blinker, 1 is right blinker, 1 is ground, and 1 is stop/running lights.... Is this correct? If so, what are the wire colors so I can re-wire the 7 pin connector correctly? If not, then what is the correct schematic/wire colors?
I am planning on towing about 175 miles round trip, and according to German law I cannot exceed 80 kmh. I have the 5 spd, so I am planning on keeping it in 4th gear most of the time...

 

Running lights are constant. It actually uses the turn signals for brakes. It lights up both turn signals at the same time when you press the pedal.

 

4pin wires..the above is correct. The 7-pin plugs have Auxilary power, Main power, and electric brake wire. That's where you get your extra 3 wires from. You only need the brake wire for electric brakes. The other 2 aren't needed unless you have a battery powered break-away for the brakes.

 

Ok...confused...so what you are saying is that if I have my left turn signal on, and step on the brake, the trailer lights amber and red lights will flash instead of just the amber flashing?

 

Depends on how the trailer is actually wired. The factory 4 way just actuates the relay's. The only to get 4 functions out of 3 power wires is to reuse the signal for something else, aka the brakes.

 

Try this web page. It'll tell you what the common outputs and inputs are over on this side of the pond.
http://www.etrailer.com/faq-wiring.aspx

The turn signal is actually just a blinking brake light. So if you brake, the turn signal over rides that side brake light and blinks.

If European trailers operate differently, then a convertor or relay type device may be required to make it work.

 

Got it working after a bunch of plug an play. For future reference in case anyone else needs it...
GRN-Right turn signal/Brake Lights
YLW-Left Turn signal
BRN-Running Lights
Black-Ground

 

Well yeah... I thought you knew that or I could have provided that for ya. If you do a search for 4-pin trailer wire diagram tons of pics come up. Ground can be black or white depending on the harness manufacturer.



Here's a diagram for every connection possible http://www.accessconnect.com/trailer_wiring_diagram.htm

 

Thanks Dirty...ya, that was what I was trying to find out. The reason was that the EU trailers have a separate wire for both left and right turn signals/tail lights/brake lights.

 

The only difference between reality and the schematic Dirty, is the fact that one blinker is using the same wire as the brakes.