I purchased a 2000 4 Star Horse trailer. I want to extend the trailer wiring so i bought a 6ft extension. I have braking system installed into truck. When i cut wiring on trailer i see no blue wire. i only have 6 wires for lights and such. I looked on trailer and it has brakes (drum) underneath. Why wouldn't have blue wire and what do i do moving forward. I am mechanically skilled but a dummy on electrical. thank you
Posted 2014-03-02 5:54 PM (#157787 - in reply to #157784) Subject: RE: Wiring issue..Please help**
Veteran
Posts: 259 Location: Topeka Ks
Sorry to tell you there is not a standard for trailer wiring. I'm guessing you already took the plug off the trailer whip. You're going to need to take a patience pill. Plug the whip in the tow vehicle and turn the right blinker on and touch each wire on the trailer whip till the right tail light blinks. Write down the color to connect and go to the next. This link may help too. http://www.etrailer.com/faq-wiring.aspxAs a trailer owner you will need to buy a test light and multimeter. Good luckJg
Posted 2014-03-02 6:15 PM (#157788 - in reply to #157784) Subject: RE: Wiring issue..Please help**
New User
Posts: 3
All my colors match and the extension (bought at Tractor Supply) has the 7th wire (blue wire) for electric braking. My trailer has 6 wires matching, but is missing blue wire for electric braking. Maybe you answered this already, but my trailer wouldn't have a blue wire/7th wire to match being it has breaks on it? Or I still need to go through each as you mentioned?
Posted 2014-03-02 6:51 PM (#157789 - in reply to #157784) Subject: RE: Wiring issue..Please help**
Extreme Veteran
Posts: 448 Location: Los Angeles, Ca.
Hello Adam340
Typically your trailer will have six wires 1.left turn 2. right turn
3. running lights 4.ground usually to frame 5. 12v positive and 6. electric brakes. The seventh wire is not usual for a horse trailer and is generally used for back-up lights. As previous post replied, a test light and multimeter are helpful. The link to etrailer wiring diagrams is really helpful and you should check it out.
Using your test light on your truck end, you can identify what pin does what.....your brake pin will show a variable response from the test light as you manually operate the brake controller. The 12v positive pin will cause the test light to glow continuously. Running light pin will cause test light to glow when the headlights are on. Left and right turn pins will show up when the turn signals are on. Ground is the only pin left. If you have the 7 pin RV fitting, the center lug is for the back-up lights and not used for your trailer.
On the trailer end, typical colors for four star trailers is as follows (but no guarantee) running lights:brown...ground:black(may also be larger than other wires)....12v positive:white ( also known as auxiliary)....left turn:yellow.....right turn:green.....elec. brake: red.
You can use a jumper and power up the different wires and see if the lights come on or you hear the brakes hum. You will need to run a jumper to the ground wire or frame of the trailer also. You may also see where the ground wire is attached to the frame and that will tell you which color is the ground wire. The 12v positive is used to power interior lights or charge auxiliary battery.
Good luck and once again, check the etrailer site for diagrams.