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Discussion Starter · #1 · (Edited)
I ran into some problems with the ECU seeing a short with my initial setup of adding led strip to the trunk. This caused the all interior lights not to function.


So how do you upgrade the lighting while still maintaining the factory on off of the door and trunk switches? This will go over everything you need, most can be found at local stores. While this write up I used the trunk as the example, it should work with whatever source you want to mimic, by simply changing the trigger wire which we will get into. Because of this I am not going to go directly into how to run all the wires ect as this would be different depending on where you adding them.
Well the factory ECU obviously does not like it when you tap the power source for any additional lighting. So we need to tap a different power source for the leds. You also need a constant on as you want the light to go on and off with whatever trigger source you choose ie dome lights, trunk, ect. The first thing you need to do is to run your power wire to the location you need from the fuse box under the steering wheel. Using a low profile add a fuse tap a constant on source (Both #19 and #20 were open and constant on in my car). Here I added a 5amp fuse which probably is not needed how I wired it, but will show you how to do this two different ways. The way I did this, because already had the parts in my garage from other projects, was to wire a female cigarette adapter to this constant on fuse and used a simple extra dual port usb car charger I had. Since the car charger already has a built in fuse, its probably not needed, but if adding an additional socket in the future, you wont have to pull it to change the fuse.

https://www.staples.com/the-install...w3XWhRZvGq1UqUoYS7990MNqlQ3az8oBoCJiwQAvD_BwE

Alternatively you can also simply wire something like this instead. You should definitely use a fuse with your add a fuse when going this route.

Amazon.com: DAMAVO YM1236 Panel Dual USB Car Charger Socket Power Outlet with Cap, Dual Port 12V-24V Quick Car Charger, for Cars, Bus, RV, Boat, Automotive Marine ATV Truck Golf Cart (Surface Mount Installation): Electronics==

This is all providing your using a standard light rope, that pretty much all have usb connectors. If not wire your power source appropriately to your application. Ive also included a video in the original thread link that shows how to turn old usb wire into a power cable/ unisex usb connector

Now dont wire the two of these together just yet. We need one more part to get this to work properly. The interior lights are all negatively switched. Meaning they have constant power and the negative is used to as the trigger. What we need is to turn that negative power source into a pos trigger source. For that we use a basic square car relay or SPST relay. If you cant find this you can get an SPSD relay which is basically the same but with an extra center pin. Basically this relay is just an on off switch.


Your negative in wire will be the wire coming from the trigger source you are trying to emulate, in this case the trunk wire. I used a simple t -tap on this and ran the wire up to the front/relay.



Your going to want to set the relay up like this:



I should not matter if you use 85 and 30 or 86 and 30 as your 12v in. Using some blue terminal disconnects, attach the two 12v+ wires to the constant 12v on you wired in slot #19 or #20 if your using my examples. I used a butt connector to bring the two wires together and then added an additional lead wire to the other end for connecting to the relay(so it looks like the letter Y). Your negative trigger wire is going to the opposite side, so if you used 85 and 30 like in the video, your negative trigger wire is going to post 86. At this point you have one post left open, 87. This is where your going to connect your power adapter to for 12v+(either the cig or usb adapter). So in this configuration, power is only being sent to the adapter when the trunk, or other source you tapped for the trigger, is opened/on. The relay is basically just an on off switch, as mentioned before.

Now lets say you want a manual override to turn these new lights on whenever you want. Grab yourself a rocker switch, anyone with three prongs you like will do.


Now you have three prongs: a ground, 12v in, 12v out. Your going to want to grab another add a fuse and tap a key on source for this. #45 works if your not using it, i used #4 which already has a 10amp and added a 3amp to the line for the switch. Your output wire on this switch will go to your wires attached to post 87. This will send power to your adapter whenever you want, bypassing the signal from the negative wire. I added the switch to an empty slot where the traction control button is. You will have to sand down and modify the middle to get the switch to fit.


So this should work for basically any where you want to add a light source. I have no afterglow on mine but its wired slightly different because I used a positive activation switch as well before realizing it was negatively switched. Since i already had it wired in, and this project fought me every step of the way(three rocker switches the first two were defective), I decided just to leave it in. If your having problems with your leds glowing even when off let me know and I will add that to the install here.

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The picture with the tr4 module is the pos on switch I used. Basically its the same as the relay, green being the activation, yellow is the 12v in blue is the 12v out. Since having this wired already I simply attached the 12v out from the relay to the green activation wire. LMK if you have any questions that i can be of assistance with.
 

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I wish I had the patience to actually focus on and understand wiring for stuff like this. Something about it just doesn't click in my head even after a really good DIY write up like this. Love the trunk LED idea though.
 

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Discussion Starter · #3 ·
I wish I had the patience to actually focus on and understand wiring for stuff like this. Something about it just doesn't click in my head even after a really good DIY write up like this. Love the trunk LED idea though.
If your interested, and have some mechanical ability, i can easily walk you through this if you like. The wiring is actually very simple now that I figured it out. Im going to add one to my footwell too as the base cars have no light down there. I realize it will activate with the trunk lights, but i dont need them to activate when i open the front doors. I dont need to see where my feet are going lol. Really its for when I need light down there so the override switch will work perfectly for me in this situation. All thats needed it to plug the light into the usb and mount it under the dash.
 

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If your interested, and have some mechanical ability, i can easily walk you through this if you like. The wiring is actually very simple now that I figured it out. Im going to add one to my footwell too as the base cars have no light down there. I realize it will activate with the trunk lights, but i dont need them to activate when i open the front doors. I dont need to see where my feet are going lol. Really its for when I need light down there so the override switch will work perfectly for me in this situation. All thats needed it to plug the light into the usb and mount it under the dash.
Might take you up on that one day. Mechanical ability, yes. Electrical, not a chance.
 

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Discussion Starter · #5 ·
Simplified down your basically only running two wires, and plugging in two add a fuses. Mine looks more complicated because, as you can see from the pics with my test light, I was in the process of figuring things out still. It's also been 110 or so here lately so working in garage not fun.
 

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Simplified down your basically only running two wires, and plugging in two add a fuses. Mine looks more complicated because, as you can see from the pics with my test light, I was in the process of figuring things out still. It's also been 110 or so here lately so working in garage not fun.
That makes some more sense. 110 is brutal. We went from 98 with indexes over 110 down to the mid 80s out here thankfully. I wouldn't be doing much in the garage if I were you lol
 

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Discussion Starter · #7 ·
That makes some more sense. 110 is brutal. We went from 98 with indexes over 110 down to the mid 80s out here thankfully. I wouldn't be doing much in the garage if I were you lol
Part of the reason took me so long to figure it out, it's just so hot even at 6am it's 90 already. aAlso
been super slammed lately. Washed the cars other day, rained next two days. Did the two daily drivers again last night.
 

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Part of the reason took me so long to figure it out, it's just so hot even at 6am it's 90 already. aAlso
been super slammed lately. Washed the cars other day, rained next two days. Did the two daily drivers again last night.
90 at 6am sounds miserable. Priorities, man haha can't argue with that. I hate getting a car clean only to have it rain the next day or so, I feel for you
 

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I took the easy way out and ran footwell lighting via one of those cheap kits that plugs into the 12v port in the center console haha wires were still easy enough to hide that way. Yours look good!
 

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Discussion Starter · #11 ·
I took the easy way out and ran footwell lighting via one of those cheap kits that plugs into the 12v port in the center console haha wires were still easy enough to hide that way. Yours look good!
Lol I know those kits I have one in my bedroom lol. I have the sub under the passenger seat and really didn't feel like wiring that stuff under the carpet for the seats. But I considered it.
 

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Lol I know those kits I have one in my bedroom lol. I have the sub under the passenger seat and really didn't feel like wiring that stuff under the carpet for the seats. But I considered it.
understandable. I had a bunch of O'Reilly's gift cards laying around so I indulged my inner F&F
 
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