I've seen many people ask how to do this so I'm hoping this helps
No one knows why Chrysler didn't put a door jam switch for the rear door so the dome lights will turn on like every other car in existance, but either way I wanted to have this luxury. Like many of you out there it's very annoying for me to have to open the drivers door everytime I want to get light in the back.
I spent at least 45 minutes just looking at the door jam trying to find the best place to mount a switch. After looking at every possible spot I realized that inside the bottom hinge is a perfect place for it. There's two slots cut in the hinge so the plastic trim will clear the hinge. I just cut the little piece of metal between the slots, ground it smooth, drilled a hole in the body, mounted the switch, wired it into the dome lamp circuit, and trimmed the plastic trim so it clears the switch. Works perfect!
I pulled the switch from the driver door jam to see if it's adjustable. It is so I bought another switch from the dealership. I also tried to get the plug that the switch plugs into but it only comes as part of the wiring harness, so I ended up soldering the wires to the switch and filling the hole with silicone to seal it.
The switch connects the ground side of the circuit. Since the rear door obviously doesn't come off when I take the doors off I wanted the dome lights to still turn on when I opened the rear door. Reason being is when I'm doorless and topless at night the dome lights will come on so I can see in the back of the Jeep. Therefore only one wire is needed as the other side of the switch grounds to the body. Since this bypasses the fuse block, wire in a 10amp in-line fuse. You can't tap into the yellow wire as many have asked because the door jam switch breaks the circuit, so the only way the rear door switch would complete the circuit is when the front door is open... Totally defeating the purpose of the switch.
The purple wire on the jam switch goes directly to the dome lights. (FYI, I tested it and with the rear door open, the lights still turn off after 20 minutes.) I am also considering another toggle switch by the wiring harness as a manual override to turn the rear lights off but I don't think this is needed. Going to drive it as it is for a while as see if I need one.
If you want the dome lights to deactivate just like the front doors when you remove fuse #4 (or if you wire in a switch like I did
) then two wires need to be ran to the back. One end is connected to each terminal on the switch while the other end is connected to the yellow and the purple wire on the drivers side door jam switch. This method does NOT
need an in-line fuse because this does not bypass the fuse block.
On to the pics...
Splice the purple wire with a wire that will go to the back of the Jeep.
Run the wire down the wiring harness, through the body plug and under the Jeep to the passenger side.
Here the wire is ran but not terminted yet.
Here's the bottom hinge for the tailgate. Keep the tailgate shut while this is off or you can really damage your tailgate. Cut the metal between the slots.