cargo light wire?

[magnethead494]

Is there anywhere under the truck or even in the truck to tap the cargo light wire somewhat uninvasively for the 2001 model year (pre-2003 redesign)?

I want to add a pair of LED lights to the rear bumper of the truck pointing out at a 45 degree angle, and have them come on with the cargo lamp or reverse lights (I can stick a diode on the double tap for that). I'll be adding a set to the trailer as well, and re-wire the reverse pin of the trailer connector to reflect the diode modification.

That way they'll come on when backing up or when the cargo lamp is on (so that we can see behind the trailer while pulling forward to re-position). But the dome light tap would be nice. Don't our trucks have a tap for it under the bed for a camper shell, or is that only for the 3rd brake light?

Also, i am aware the cargo lamp is a toggle ground setup. For what I am doing, that is fine, I can relay it to do what I want.

 

[magnethead494]

I'm seeing two things but I'm not sure what years they apply to- the top right blue/white wire in the MBEC and the bottom left double orange in the MBEC. Apparently if you bridge those 2 across the coil of a relay, the relay will be in parallel with the cargo lamp (which retains the 10 minute lamp timer). Another post I found said that tapping the middle contact of the cargo lamp switch should also supply a ground, and removes the 10 minute timer. But I need to look into it more via the multimeter.

My thought is to take some twin lead, connect to the orange and blue with yellow trailer taps (already have), find a grommet, and run the twin lead back to the trailer connector. From there I can add the relay, using trailer purple for power (pin 30), and sending that power to my new lamp wire (white). Then I can take a diode, and jump from the white wire to the factory reverse light pin of the trailer connector, and branch the white wire to the reverse pin of the trailer connector. Thus, when cargo lamp is on, power flows from purple 12V through relay to white wire, to truck LED's and trailer reverse pin. When cargo lamp off and truck in reverse, the trailer reverse wire feeds through the diode to the white wire. when cargo lamp is on and reverse lights are on, the diode becomes neutral and everything lights up.