can not get wiring right on flatbed truck bed

[grasshopper1]

I bought a used J&I flatbed for my 2003 dodge truck. It came off a 2004 dodge. As you probley know the wiring colors are different and we didn't check that before cutting them. So after all night of working on it, we ended up putting a 4-flat plug on the trailer plug connector to power brake and turn. The back up and park lights are wired to the factory wiring. Later I hooked up turn and break lights to the factory truck wiring. Both hooked up canceled out turn, so the problem is going from factory dual filament bulb to seperate circuits. I'm no good at wiring, so any help would be great. Will the lamp out indicator need to be reset after correct hook up. Oo.

 

[jelag]

at this point your not specific enough to help..... once you have a good ground between the new bed and the frame of your 03 it should be a simple task to sort out the LT, RT, tail lights and reverse with either a test light or volt meter and connect the wiring...

 

[PDM]

I think you can download the "body builders guide" for free at the dodge site.



I believe the wire color codes for what you want are in that manual.



http://www.dodge.com/bodybuilder/

 

[grasshopper1]

The "body builders guide" doesn't show 2003 manuals. Thanks for the help.

 

[robertyoke]

If you get the wiring correct then the lamp out indicator will go out.

get a test light and you can figure out what wires are for what.

-robert

 

[McCRam]

I just went through this a couple of months ago with our 98. I had the wiring diagrams and color codes, but in the end, I couldn't have done it without a test light. On the bed, I ended up building a whole new harness, got tired of trying to map out which wire did what. I used a 7 way trailer wire to build most of that.

 

[bighammer]

The "body builders guide" doesn't show 2003 manuals. Thanks for the help.

I have the 03 manual. Let me know if I can help.

 

[jelag]

After reading your posts, and your note to me, here are my suggestions... for some of us this is very straight forward... . you seem to be having some problems and I've tried to reduce this to basics... . if you have problems with this please either email me again or consult professional help...



1 - are the lights on the flat bed LED's or standard bulbs... .

2 - do you have a 12 v test light or volt meter... .

3 - are the tail/stop lights sealed units with a 3 wire pigtail coming from them... .

4 - if 3 is yes... . look on the back of the sealed units and they are labeled tail, stop, ground... make sure that all ground wires are grounded to the bed... we usually weld a stud to the bed to bolt ground wires to them... we usually have 3 or 4 of these on the bed... if not use a drill motor and put a hole someplace in the bed where you can do this where it doesn't show... and you can get to it to clean it... make sure that this is not in the spray area of the rear wheels...

5 - once you've decided that you have a good ground and that all the bulb housings are grounded correctly run a 12 volt wire from the battery... . to each of the wires on the bed... . take some masking tape and apply the 12 wire from the battery to each of the wires on the bed... . label what lights up... . tail lights are dim red, stop turn are bright red, back up lights, clearance lights...

6 - Once you decide what each of the wires go to on the bed, now take the 12 v test light and check each wire coming from the truck wiring harness... . do the same with the truck... either right down the wire color and what comes on... . ie: turn on the head lights one click... so that the clearance lights and tail lights should be on... mark the wire or connect them to the wires you've identified as the tail lights clearance lights. .

7 - turn off the lights, and turn on the left turn signal... find the wire that flashes the test light and connect that to the wire you've identified as the left turn bulb, do the same with the right turn as well... .

8 - now do this with the back up lights by putting the transmission in reverse and finding the wire that lights the test light... . connect this to the back up lights...

9 - if you are using LED's as stop tail lights and clearance lights there might not be enough current draw to shut off the bulb out light on your trucks dash... if this is the case you need to have someone sell you common sealed units that bulbs in them and replace the LED's or find someone who can help you work through the installation of a resistor to draw additional current to shut down the light... .

10 - using ohm's law, with an ohm meter you can measure the current draw of a bulb and compute the amount of resistance you'll need... I personally suggest that you just remove the sealed LED's and replace them with sealed bulbs...

11 - when you make or check the connections on the sealed units or the back of the bulbs..... get some vasoline, or dielectric grease to coat the connections to prevent electrical damage to the connection... .

12 - the common connection between bulb or sealed unit and the wire are dissimular metals and with electricity flowing through the connection and some spray from the road these connections will fail...



Hope this helps...

 

[grasshopper1]

flatbed wiring

The lights are not led, they are sealed with the 3 wire. I have a 12-volt test light and a volt meter. The headache rack has 2 lights on the right side and two on the left. One red (stop, park, turn) and one clear (reverse), same as on the back of the bed. Some flatbeds have have stop and tail as one and turn as one and reverse as one. How do I tie those circuits together, for my bed sense they are different? Like I said, when I did it before, the turn canceled out when break and turn where on, at the same time. Thanks for the help, I really appreciate it. Oo.

 

[jsdan]

The original lights have a seperate wire for turn signal and brake light (3 bulbs in oem tail light assmb. -one turn, one brake, and one reverse).

You will need a tail light covertor to get your turn/brake signal into one wire if your taillights have one bulb each with two filament bulb like a 1157 bulbs.

 

[bighammer]

Couldn't you tie into the trailer light circuit for one and the rear harness for the other? I thought the trailer harness could go either way.

 

[jsdan]

You could tie into the trailer 7-way circuit and the lights would work but you will lose your seperate fuse protection from truck/trailer lights.



Also if you pull a trailer with alot of lights you will be putting more load on the 7 way circuit with additional truck lights added in the mix.

 

[rockingtf]

Can someone please explain how to differentiate between the 7 way trailer light circuit and the truck lights. Is it just a matter of pulling the fuses and checking wires with a light. My pickup came with a hack job done on a flatbed install(all wires rearward cut at the back of the fuel tank.) I went through and got all lights working properly but the bell rings/lamp out flashes in the cab any time I put a turn signal on. If I apply brakes with the turn signal on, the indicator/bell will quit. My guess is I am using some part of the trailer light circuit, and some part of the tail lamps. I am running all sealed lamps (3 wire) with no LEDs.

 

[Donny23]

I wire flatbeds regularly on all pickups. Dodge by far was my biggest first nightmare. However, it is actually very simple. Dodge has separate wiring for the left and right except reverse. You will have LH tail, stop, directional and RH tail, stop and directional. Reverse(usually-purple with black stripe) is the only shared. You will also need to place a 6ohm/50W resistor in series with each tailboard light except reverse. If it equipped the headboard cannot brake illuminate. If attempted you'll develop a periodic pulse in the lights(all), due to feedback.

 

[Donny23]

A 7-way is different but simpler. Yellow to LH directional, Green to RH directional, White to ground, Brown to tail, Red to 12V+ Acc., Purple to Reverse, Blue to Electric Brake. Each directional also is brake for that side. You'll see with a meter. Positive probe on directional wire and watch it pulse as directional, then hit the brake and it goes to a steady voltage. Obviously Black/GND probe to ground when doing this.