Tailgate Dome Light Activation Switch

I'm sure there are 12V timers on Amazon.
I'm sure there is a ready made timer out there that would work for this, although the only options I saw have very short trigger times (seconds not minutes).
I once configured a small RC network that would charge when the door was opened and then discharge through an LED over 10-15 seconds after the door was closed, so I could see to install the ignition key in an old Porsche... I miss the good ol' days when you actually had to make shit.
 
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Here's one...
 
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I suppose there is some risk that I leave the switch in the "always on" position, but I'm not worried about it. The timer is an interesting idea, but I don't want to over complicate the wiring. Maybe I'll get a reminder sticker to put above the switch.

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So I’m in the middle of doing this mounted the tailgate switch now to the glovebox I have off rent color wiring. 2004 LJ here.
Passenger door plunger has these two wires. Black and yellow and pink and yellow. Neither of which match the OP’s color or descriptions.

I’m not a huge electrical guy so some guidance here would be appreciated
Thanks in advance to someone who is smarter than me!

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Also being that this is right by the fuse panel can a fuse tap be used instead of cutting into factory wiring?



I know it’s not a big deal but I’m not there yet!
 
I compared the 2006 wiring (OP's) and the 2004 wiring (yours) in the FSM's. For 2006, YL/DG is shown as
"Door Ajar Switch Output". For 2004, this same wire is YL/BK. OP says this wire is the ground. The other wire (VT/YL in 2006 and TN/YL in 2004) is labeled "Door Ajar Switch Sensor". OP says this wire is the positive supply and is the wire you will tap into. Hope this helps.
 
I have always felt the TJs/LJs have been lacking when it came to having a pin-switch for the tailgate that activated the overhead dome light especially for those who remove the rear seat and use the back for open storage. I have seen others look for the same thing, but I have been unable to find a definitive guide. So here is a simple How-To on how to install this feature with all the trial and error removed.

Install Time: 30-45 minutes when you have all materials and moderate electrical experience

**Don't forget to either disconnect the battery or remove the #4 Fuse for the Door Lights to protect system while installing**

Materials:
-(1) Glove Box Light Mod)
-(1) Roll of wire (16 Gauge, marine grade due to not using a top in the summer)
-(1) T-Tap with Connector (16 Gauge)
-(1) Slide Connect Female (16 gauge, I used heat shrinkable weatherproof type)
-(1) #8x1/2" self-tapping screw (or use a similar size bolt with matching size drill bit for the mounting hole on the pin switch)
-Mounting Pads (I suggest these because America)
-Zip Ties (see reason above)
-Shrink Tubing (Optional, but adds to longevity)
-1/4" braided wire sleeve (Optional, but adds to longevity)

Tools
-Power Drill
-3/8in Drill Bit (for metal unless you like messing up your wood bits)
-Heat Gun (for shrink tube)

** Note: You can buy all these products locally and are just suggestions. There are many ways to build the same system, you may have a better idea to connect components. The only part I bought online was the pin-switch**

Installation:
I first went to my tailgate and looked at mounting location possibilities. I was originally going to mount the pin switch within the hinge, but I plan on switching to other Heavy Duty hinges in the future. The next best place was on the hinge-side lip of the tailgate where the lip meets the weather stripping. I chose the hinge-side because you aren't slamming that side shut like you do on the handle-side (so the switch should last longer).

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After finding my switch mounting point, I then went to the passenger side door pin-switch and popped it out to look at the wiring. You will see two wires. Mine had a Yellow/Green wire and a Purple/Yellow Wire. The Yellow/Green is a Universal Ground wire code, so I assumed the Purple/Yellow Wire was the positive supply (the wire where you will tap into).

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I opened my roll of red 16 gauge wire and made an approximate cut that would allow me to remove excess length later after finalizing installation. I stripped one end and crimped the connector that attaches to the T-Tap (usually comes in sets with the T-Taps). I stripped the other end and crimped on the Slide Connect (female) that would attach to the Pin Switch tab. At this time I also slipped on the braided wire sleeve.
I opened and removed my glovebox while tugging on the door-switch until I saw the matching Green/Yellow and Purple/Yellow wires moving by the fuse panel. I then took the T-Tap and clamped it onto the Purple/Yellow Wire and plugged in the matching connector that was previously crimped above. Make sure you use pliers to securely attach the T-Tap; you will hear the enclosure snap and lock in place.
Connect the length of wire using male-side T-Tap connector and use zip ties to secure the wires and prevent future tugging.

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I ran the length of wire to the rear of the vehicle following the body tub-edge on the passenger side to where I would mount the Pin-Switch. I marked the exact spot for the pin-switch and drilled a 3/8" hole for the main body of the pin switch. I pushed the pin switch through the hole and then installed the mounting screw using a self-tapping screw (or drill a hole and use a small bolt).

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You will see notches cut into the pin-switch plastic body, I cut it down to the lowest notch due to the small space in the area mounted. I made sure the rubber boot was installed correctly around the outside of the switch and that the tailgate closed correctly.

I then plugged in the Female Slide Connector to the pin-switch tab. I replaced the #4 Fuse and tested the system.

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The pin switch worked perfect and each door activated/deactivated the Dome Light independent of each other.
At this time, I took the 1"x1" cable mounting squares and zip-ties and finalized my wire routing making sure it is unseen and out of the way. I also cut the wire to the prefect length and stripped/re-crimped the pin-switch side of the wire after routing it.

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Your tailgate will now turn on your courtesy dome lights.

Post any questions below or feel free to PM me and I will add/update the post if I am missing anything.

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Is the purple yellow wire (the one you tapped into) the fused wire? Is there a way to tap into this via a fuse tap at fuse 4?
 
The wiring diagram on page 8W-44-4 of the 2004 FSM should help you out. I'm not great at reading these, but it looks like the YL/BK wire runs to fuse #4.
 
Is the purple yellow wire (the one you tapped into) the fused wire? Is there a way to tap into this via a fuse tap at fuse 4?

No, actually the door defeat fuse (#4) is on the ground side and is just used as a switch/jumper. The purple wire that you tap into from the instructions in this post is on the upstream side of the existing door switch and is what the computer is looking for to be grounded in order to turn on the lights. Tapping into the yellow wire won't work because it will be isolated from the sense wire if the passenger door is not open. In order to be disable-able via fuse 4, you'd need to use a different kind of switch that uses two wires to go from the sense side (purple) back to the yellow side, through the fuse and to ground there.

The easier thing to do would be a disable rocker switch in the cargo area in the seatbelt shroud. Some pictures in this thread show people adding dedicated on/off switches there, but if you put that in the line that you run from the door switch to the fuse box, then the switch becomes "auto/off" instead of "on/off". Thus, it'll open with the doors if "on" and if off, it will let you keep the tailgate open without the light being on. This is my preference - I want it to turn on when I open, but sometimes I leave my tailgate open for hours while loading or drying out, so I want to be able to defeat the lights sometimes.

Doing this also means you get a separate defeat switch for the tailgate and the doors, so if you're running doorless you can retain the auto tailgate while you want (fuse out) and then also defeat the tailgate when needed with the actual switch.
 
No, actually the door defeat fuse (#4) is on the ground side and is just used as a switch/jumper. The purple wire that you tap into from the instructions in this post is on the upstream side of the existing door switch and is what the computer is looking for to be grounded in order to turn on the lights. Tapping into the yellow wire won't work because it will be isolated from the sense wire if the passenger door is not open. In order to be disable-able via fuse 4, you'd need to use a different kind of switch that uses two wires to go from the sense side (purple) back to the yellow side, through the fuse and to ground there.

The easier thing to do would be a disable rocker switch in the cargo area in the seatbelt shroud. Some pictures in this thread show people adding dedicated on/off switches there, but if you put that in the line that you run from the door switch to the fuse box, then the switch becomes "auto/off" instead of "on/off". Thus, it'll open with the doors if "on" and if off, it will let you keep the tailgate open without the light being on. This is my preference - I want it to turn on when I open, but sometimes I leave my tailgate open for hours while loading or drying out, so I want to be able to defeat the lights sometimes.

Doing this also means you get a separate defeat switch for the tailgate and the doors, so if you're running doorless you can retain the auto tailgate while you want (fuse out) and then also defeat the tailgate when needed with the actual switch.
Thank you for the very detailed response. I dug into this more after I posted and figured it all out, it works perfectly. I would say it’s one of my favorite things I’ve done to the Jeep.
 
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No, actually the door defeat fuse (#4) is on the ground side and is just used as a switch/jumper. The purple wire that you tap into from the instructions in this post is on the upstream side of the existing door switch and is what the computer is looking for to be grounded in order to turn on the lights. Tapping into the yellow wire won't work because it will be isolated from the sense wire if the passenger door is not open. In order to be disable-able via fuse 4, you'd need to use a different kind of switch that uses two wires to go from the sense side (purple) back to the yellow side, through the fuse and to ground there.

The easier thing to do would be a disable rocker switch in the cargo area in the seatbelt shroud. Some pictures in this thread show people adding dedicated on/off switches there, but if you put that in the line that you run from the door switch to the fuse box, then the switch becomes "auto/off" instead of "on/off". Thus, it'll open with the doors if "on" and if off, it will let you keep the tailgate open without the light being on. This is my preference - I want it to turn on when I open, but sometimes I leave my tailgate open for hours while loading or drying out, so I want to be able to defeat the lights sometimes.

Doing this also means you get a separate defeat switch for the tailgate and the doors, so if you're running doorless you can retain the auto tailgate while you want (fuse out) and then also defeat the tailgate when needed with the actual switch.
Something else that can be noted when I leave my doors open for an extended period of time my dome lights turn off. Whether it is from driver/passenger door or the rear tailgate door I added to the system. Either way after the doors are open for I’d guess around 10 minutes the dome lights shut off.
 
I know this is an old thread so maybe nobody will see this question, but…

Is there a way to tap into these wires to get a signal (to trigger a relay) when the dome light goes on? I’d like to have a light that I can turn on only when the doors are open.
 
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I know this is an old thread so maybe nobody will see this question, but…

Is there a way to tap into these wires to get a signal (to trigger a relay) when the dome light goes on? I’d like to have a light that I can turn on only when the doors are open.

I used T-taps to tie into the footwell lights and added LED tape light along the edge of each door opening.
While I made my lights turn on with the door pin activation, you could simply add a switch to the +12 side of the circuit to create what you are trying to do.

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Looks good. I used a posi-tap but didn’t register voltage when I tested it. The courtesy light lights up, so I wondered whether something else is going on.
 
Looks good. I used a posi-tap but didn’t register voltage when I tested it. The courtesy light lights up, so I wondered whether something else is going on.

The sense wire is grounded when the doors are closed and float high (but provide basically no current) when they're open. You won't want to drive a relay from it. Instead tap the actual positive wire from one of the existing lights, as @WestCoastDan did.
 
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It turns out that you can’t tap the light’s wire, because (as I probably should have guessed), the door switch doesn’t activate a relay or anything, it just grounds the power to the light and activates it. So the power wire to the light is always hot, and the ground is only grounded when the door opens.

My solution was to use a ground-switched relay, as follows:
– tap the power wire (always on) and connect it to both the power (pin 30) and the signal (pin 86)
– tap the ground (switch-operated) and connect it to the relay’s ground pin (85)
– feed the relay’s output (pin 87) to my relay box to operate the courtesy lights.

I’m essentially using two relays in this setup because I have a custom switch panel and relay box, which simplifies most of my wiring. The power from the courtesy lights is pretty low, so I didn’t want to try to pull too much current through those thin wires to additionally operate four rock/courtesy lights. And the point of my relay box is to avoid running power everywhere. My switches have a few custom (dt-connector) wiring harnesses that keep everything pretty clean and well-labeled.

So all the in-cab relay does is send a signal, and the courtesy lights are wired up with everything else under the hood.
I was prepared for some stutter when the courtesy lights dim, but the relay just clicks off, no problem.

This is also handy because I plan to have the switch for the rest of the rock lights also trigger the under-body courtesy lights. That’s a project for another day; but when I do it, all I’ll need is to connect one signal wire to the other (with a diode).

I also have a time-delay relay that powers lights at the tailgate for camping. It’s currently triggered by the ignition (so it stays energized for X minutes after the ignition is turned off), but I may change that to be triggered by the courtesy lights as well. It is really handy when setting up camp and cooking.
 
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