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Our 2012 f-150 7 pin trailer works sometimes. For example I used a multimeter to test if it was getting any volts. It reads roughly 13 volts in the garage and 0 when i park it in front of the trailer. It sounds like there is a short somewhere, but the wires I can see look good. It would be nice to not have to pay if its simple.
The only difference is that the garage is sloped a little while the area in front of the trailer is fairly flat. And I actually tested it again and it worked the entire time this time
Any chance maybe you just weren't making good contact or your multimeter was on the wrong setting when you read 0V? If not, I'd still use some alligator clips and start moving that harness around a bunch to see if it drops off.
ok, actually i found out that this wire(brown) turns on and off with the headlights, so that's why it worked in the garage because the headlights were set on automatic. So that problem is fixed.
However the trailer lights are still not working, so there must be an additional wire that needs power. All the wires have power except for the blue one. Trying to figure out how to get the blue one power, which I believe is the brake control or electric brake wire.
Either way, black should always be hot 12V. Blue won't have power unless you have a brake controller and are pressing on the brakes. I don't know what grey would be, unless it's actually white but is discolored. White is your ground. Yellow and green are your turn signals. Brown will be running lights.
Another thing you can do is check continuity between the truck's white wire and the truck frame and the trailer's white white and trailer frame. You want to see shorts here.
The only thing that might be causing a problem is that I might have disturbed the original order when i was taking wires apart. So the wires might not all be in the same order to the blades.
When I get home tonight, I'll throw up a wiring diagram for you. Either that or you can just go to google.com and search for "7 pin trailer wiring diagram."
Unless I'm missing something, your two diagrams show exactly the same thing because it's a standard.
Stop randomly mixing wires before you burn something up. Make your truck fit the standard. Have someone else hit turn signals, brakes, running lights, etc while you test the pinout to make sure you're getting what you expect. Then make sure the plug on the trailer is wired up correctly, per the diagram. Once again, it is a standard.
Alright, now that I'm in front a computer so I can see something...
With the colors you say you have, I'm going out on a limb and assuming this isn't a factory plug and harness? With the colors you say you have, I would go out on a limb and assume red is 12V constant and the grey is your backup. You can easily test this with a meter though.
ok, that looks good. I wired mine like the 7 blade SAE standard, but I'm still having problems with my blue wire getting 6 volts while the other wires are getting 13 volts. I believe this is causing my 7 to 6 pin adapter to have one pin without any volts on the 6 pin side while the other 5 pins have 13 volts.
Is this a factory brake controller or aftermarket? Are you testing it will the controller set at it's maximum using the manial switch? If not, do that. If you're getting 12v at the controller output but not at the socket pinout, check your termination there for corrosion or a loose connection. If you're getting less than that but are getting 12v in at the controller, you have a bad controller.
It's a factory brake controller.
How would I be able to ditch the adapter?
Because the trailer is a 6 round pin and the f150's are 7 blades.
Also where's the socket pinout and controller output for the brake controller?
I've been testing the brake controller with the max and min and it doesn't seem to make any difference in volts.
