06 F350 Trailer lights...only has running lights.

WishIhada7.3 · #1 (**permalink**) 11-04-2009, 09:08 PM

I have a 06 F350 with a Dump body...When the trailer is hooked up it only has runner lights..Im using a 7-pin plug in tester with the LED's. And backing it up with my voltmeter. I have NO power for the turn signals and brake lights(left and right)....i have checked ALL the fuses both under dash and underhood. however i am UN-sure of the relay location...should there be a relay for each side? 2? any help would be great!

twags6 · #2 (**permalink**) 11-05-2009, 01:13 AM

Is this the first time you used the connector or has it worked before? Left turn/stop and right turn/stop should each have its own fuse. IIRC, the 99-03's have the relays under the dash below the radio, your truck may be different though. Find the two fuses I mentioned and check them with an ohm meter. Sometimes they look good but aren't.

twags6 · #3 (**permalink**) 11-05-2009, 01:16 AM

Ok, just looked up your owners manual. If you have a copy of it, open it to page 212. There's a diagram of the fuse box under the hood. Relay 201 is for rightt turn/stop and relay 202 is left turn/stop. You can swap the a/c clutch relay in spot 203 with one of those to verify that they work. The fuse for both relays is #9 in the same box. Its a 20 amp mini fuse, those are especially hard to see when blown.

If you don't have a copy, you can download one here https://www.fleet.ford.com/maintenan...ls/default.asp

WishIhada7.3 · #4 (**permalink**) 11-07-2009, 07:49 AM

I can tell that some of the fuses have been replaced before...but all checked good with my meter. The lights use to work...when i turn the hazards on there is 1 relay clicking in the fuse panel in the engine bay....thats it..are the trailer lights on a different relay from the flashers on the actual truck? all fuses in that panel tested good. and all lights on the actual truck work..........

BPofMD · #5 (**permalink**) 11-07-2009, 01:05 PM

Wish, read "twags" post to you right above your last post! Check the Relays! Turn signal and flasher relays are different.

twags6 · #6 (**permalink**) 11-07-2009, 04:40 PM

With the 4-ways on, there should be two relays clicking in the under-hood fuse box. The relays provide dedicated power to the trailer so if something happens there, it wont take out the signals on your truck.

Can you tell which relay was clicking? Its possible they could still be bad even if it clicks. Did you try swapping the one I mentioned?

DanzbigA250 · #7 (**permalink**) 11-07-2009, 06:56 PM

Curious to see what you have going with yours too. I have a 2006 F-250 and I have the same problem, I have running lights, but no turn signals or brake lights. My trailer has brakes on it and they won't work unless I manually use the brake controller. I'd be surprised if both relays went out at the same time. Any added help is appreciated.

LCDR Dan

WishIhada7.3 · #8 (**permalink**) 11-07-2009, 08:45 PM

found the problem 2 actually............

#9 fuse had a spread out terminal on the fuse panel....from some one wiggling the fuse the wrong way during removal. It still tested good with my meter but the way i found it was removing it and saw the fuse prongs were burnt....so after i fixed the fuse terminal both relays started clicking....now i had left side but no right.....traced that to a broken wire close to the 7-pin female connector at the back of the truck.............thanks for the help!!

DanzbigA250 · #9 (**permalink**) 11-07-2009, 10:00 PM

Hmm, great now I have to go check all that crap tomorrow, wonderful.

LCDR Dan

twags6 · #10 (**permalink**) 11-08-2009, 12:51 AM

Dan, do you have a factory installed brake controller or an aftermarket add on? The brakes not working when you apply the pedal sounds like the controller isn't receiving a signal that you're on the brakes. On an aftermarket controller, its a simple wire going from the brake pedal switch to a terminal or wire or the controller. No idea how the factory one is hooked up though.

DanzbigA250 · #11 (**permalink**) 11-08-2009, 10:28 AM

Yep, it's the factory controller. Thinking I may have to take it in somewhere to have it looked at. Need to go through all the fuses first though. maybe today, the weather's nice up here.

LCDR Dan

tfalk · #12 (**permalink**) 11-08-2009, 11:32 PM

Going through something similar with my 06 with the integrated brake controller right now. Everything worked fine (or so I thought?), installed new brakes on my trailer and it seemed like they weren't working. Checked the 7 pin and only getting 1 volt to the trailer brakes when I step on the pedal with the controller set on 5, hitting the slide gives me 7 volts on the back.

I read a couple of posts on various boards that the integrated controller doesn't apply much voltage unless you are going over 15 mph? If I hold the slide, the trailer brakes lock up so I'm assuming it's working correctly. I have to take the trailer out next week, only have some lawn furniture to move so it shouldn't be a problem either way.