Nick Dodge

I just put a flatbed on my 03 dually and am having trouble with the tailights. I bought a t-one kit so that I wouldn't have to cut the factory wires. I get a lamp out indication with both blinkers and brake light even though they work. I also get a high speed flash while braking along with the lamp out indicator. I have two wires from the harness that I have no idea what they do. To recap-blinkers work fine by themselves-lamp out indicator on
blinkers rapid flash when used with brake-lamp out on
brake works fine but lamp out indicator on
tail lights fine -no indicator
back-up works fine-no indicator

HELP PLease!!!!

wheelo90

I also recently put on a flatbed on my truck. I used LED lights, and I wired them up to the old wires that went to the original bed lights from the original bed. In other words, I cut the wires to my old lights, and wired in the new lights right to the end of the wires. I hope I did not confuse you more!
BTW, My turn signals are wired up into my break lights do to the fact that the tail light has 2 purposes, one for breaking and another for Turn signals.
You might try a new relay that goes under the dash in case the old one died!
Wheelo

Jeremy Cusick

Also, if you're using LED lights, some flashers will not see enough load (amperage draw). You'll need an electronic flasher... they might even make a special one for LED lights, but unsure on that one.

Nick Dodge

I am not using led lights just a standard stop,tail, turn, and back-up. Do you recall the funtion of the wires and how you connected them and did you have any left. I am assumming my 2 loose wires have a function and are needed to complete a circuit but I don't know how or where to put them. The t-one connector I used just gives me a pigtail to work from so i can leave the harness untouched. I would think it would be the same as wiring it straight.

wheelo90

Alright this is what I did on my truck,
I had someone press the brake peddle while I had a tester to see which one had power being sent through it.(making this the brake wire) Then I found the wire to the turn signals by testing to see which one was my turn wire.
My LED lights have 3 wires on them (one to ground, one to brake lights, one to turn lights) I wired them up to the wires on the back of the lights.
BTW, my brake and turn signals are on the same design(turn signal is tail light and turn light)
I hope I could help ya,
Wheelo

Racer9

I'll have to correct this, maybe you just misstated what you meant, but those lights that have 3 wires are for, ground--brake/turn--clearance. The brake/turn wire is the same one.

Make sure the bed is grounded to the frame. A large percentage of electrical trouble is due to bad ground.

Dusty Ratcliff

the problem you have is that the 03-up trucks use two different bulbs in the taillight for the brake/turn & for the park light, their is a way to make them work, but I can't recall what it is, they make a relay or distribution box or something to remedy this problem, check with any local places that sell trailers or beds they should be able to point you in the right direction, I'm thinking that running the wires for the park & brake/turn together doesn't work (had this same problem on my cousin's 03') keep checking someone will chime in with the answers, sorry I could only explain the problem???? Dusty

Nick Dodge

Still working on it. Dealer said they could probably do something in the computer to fix it???????? Sounds like he was guessing.