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2003 (12/02) 2500 QCLB Flatbed install - wiring questions

4217 Views 4 Replies 3 Participants Last post by  MET1288
Hey all, newbie here with a 2003 5.9/5spd 2500 QCLB 4x4 (12/02 build date). I'm installing an aluminum flatbed (Aluma 81096) and it's time to tackle the wiring. The bed is pre-wired with all LED lighting. I'm new to the dodge world and am not overly familiar with the ins and out of the lighting system dodge employs. I have read and read and read enough to really confuse myself.

Here are the basic questions I have:

-What circuits will need resistors (or is there another way)?

-How should the lights be grounded? I was told its easy to fry expensive parts if they are grounded wrong.

-Is there anything in particular I should be aware of or avoid?

-Where can I find wiring schematics if needed?

Thanks for any help you can give! The install has gone great so far!
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If the bed is pre-wired they should have a ground wire in their loom... I'd run it to the frame... I'd also run a second ground, at least 12 gauge to the engine compartment and tag one of the grounds that the factory uses there....

I know that one some of the trucks you need a resister across the turn signals to make them flash at the correct speed...

I have a flat bed on my 05, I used to run a small fleet of 4-5 trucks... I don't use LED's... we had a flat bed rear ended in the winter during a snow storm... the snow covered the lights... and than it was hit... we took out and removed all the LED's and moved back to the sealed 4" units.... there's enough heat with the tail lights running during the day to keep them melted off...

On all our trailers we used the wiring for the trailer plug to power relays on the trailer for the lights... we ran a 10 gauge wire to the trucks connector, and than through the plug to the battery on the trailer... we installed a box on the trailer and put a relay for the tail, turn, backup lights... the only circuit not on a relay is the trailer brakes... this keeps the load low on the truck wiring... geez those are small wires....

there's nothing at the back of the truck that I know you can hurt with a poor ground except for a circuit not lighting correctly...

We found some 1/4" thick rubber we used as a cushion-er between the bed and the frame... we actually added some brackets and fasteners to keep our beds secure to the frame...
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Thanks for the info! I just want to make sure I don't have a "lamp out" light activated or damage the control module. I read somewhere it's easy to fry a lighting controller.... have any input on that? I'm certain I'll need resistors to solve the "lamp out" and rapid flash problems.

As for mounting, I custom welded mounts that provide a level mounting surface and plenty of attachment points. The bed actually goes on this weekend once some paint work cures.
Mine is 10-02 and I didn't do anything special. I reused all the oem hot and gnd wires. My tail/stop/turns are incandescants and the marker/plate lights are led and no rapid flash or light out. All my leds must have a resistor built in and they were all designed for 12vdc. Craig

My flatbed came with all LED lights including tail/stop/turn. I'm told those are the ones requiring resistors for correct flash and to satisfy the lamp out indicator.

Can anyone tell me the correct resistor size for each? My OEM tail light/circuit board assemblies are long gone so any information would be helpful.

I'm also hunting for a wiring schematic for the tail/stop/turn system. The bed should be mounted Sunday, so its all wiring now!
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