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My red and cheap interior illumination kit.

11K views 27 replies 9 participants last post by  Brainanator 
#1 ·
So I really liked the look of the interior illumination kit, but I didn't want it to be blue with most of the dash being red. I also didn't want to pay $130 for some LEDs, some wire, some plastic LED holders, and a light diffuser for the cup holder (which I might be will to pay for on it's own...)

So I decided to order some LEDs from superbrightleds.com and build my own kit. I ordered them with the resistor soldered on to make it easier on my self. Each one came with a simple LED holder, and I ordered 100' of black/red zip wire (like speaker wire, the two wires are connected).

Now I did cheat a little. My car has the door sill lights and puddle lights. So the wiring harness was already next to the dash in the passenger footwell. I just used my volt meter to see which pair of connectors changes with the dimmer switch and wired the LEDs to that.

I filed down the lens of the LEDs in the footwells to dim them slightly and diffuse the light more. The LED in the center cubby hole is a 360 degree LED, so it's already dimmer and diffused. I left the lenses on the LEDs for the cup holder since I wanted all the light on the diffuser ring.

As for the diffuser ring, I used a polycarbonate rod. I heated it in the oven at 200F (I think) until it was soft, and then I quickly smashed it into the diffuser ring area. I think I need to take it out and try to polish it, I'm not 100% happy with this part yet. I may also try some clear vinyl tubing.

Another thing I did while having the dash apart was the parking brake mod, so now the dang system won't lock me (or my passenger) out when I'm driving. I also used a SPDT (3 way) switch so I can use the reverse camera whenever I want. Using the SPDT switch allows me to keep the reverse lights off when I'm manually looking out the back. Probably the hardest part of the day's work was figuring out WHERE to put this switch... I ended up putting it on the side of the driver's footwell. This way I can replace this small trim piece if I ever need to sell the car (hope not) and the switch it hidden out of the way for everyone else. I did see some people use the interior fuse door for switches, and that was very tempting, but I didn't want to destroy the fuse diagram inside the door just in case. Where I mounted it was also near my main wiring harness, so it was very convenient. I wired it up so the indicator light on the switch is OFF when not in use, and dim when in use. Normally it would be bright when in normally open, and dim when actuated.

Last thing I did was add a pair of powered USB ports. This eliminates the need for an adapter clogging up my cigarette lighter hole. It allows for 2 USB devices to charge at the same time. Has a nice cover when not in use.

I also mounted my scangauge on the roof of the cubby hole. I used 3M allweather "dual lock" velcro. The "velcro" stands out a little bit, so I might think of a better way to mount it in the future. The scangauge cable comes out the "sticky hole".

Let me know what you think! If you have any questions ask away!



















Red LEDs (used in footwells and cup holder)
Red LED used in cubby (need to solder on you own resistor to use the 12V power)
The switch I used If you aren't sure how to wire this up to keep your reverse lights off I can make a diagram or something.
Zip wire
 
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#2 ·
I think tomorrow I will add a relay to make the LEDs turn on with the puddle lights. Seems pretty dumb that foot well lights don't illuminate when getting in/out of the car. I didn't check this part when I was poking around with my multimeter. At lease all the wiring will be right there in the footwell so I don't have to tear everything apart again...looks like I've been wrestling tom cats all day because my arms are so scratched up!!
 
#4 ·
Well, I pretty much outlined in my post. The only other information you need is to use a 1/4" drill bit for the LED mounts, a 30mm hole saw for the USB adapter. For any of the ignition switch 12V I just used the center console cigarette lighter wires (the one in the armrest).
If you follow the other guides people have posted for the OEM interior illumination kit it's basically the same thing, just need to drill a small hole instead of snapping in the OEM LED bracket. The 360 degree LED I used didn't fit in the LED mounts, so I used hot glue to hold it in place, same with the LEDs in the cup holders. the hot glue let me adjust the aim easiest after popping a hole in the outside of where the OEM LEDs would snap into.
My advise is to dedicate a whole day or 2 (took me 6 hours with all my soldering/wiring/drilling). Just go slow. When you're putting stuff back together count screws and holes and be gentle.
 
#5 ·
Where did you find that two port USB outlet with the cap? I like that.

thanks
 
#7 ·
2 port USB charger
I thought $20 was a little steep for it (yes, I'm cheap), but Blue Sea seems to be a top notch brand, and most the reviews are stellar. I also didn't want to be plugging my X hundred dollar electronics into the cheapest thing I could find.
The mounting instructions call for a 30mm hole, but I didn't have a hole saw of that size. I ended up using a 1 1/4" hole saw and I wouldn't not want to go any bigger. 1 1/8" might be ideal (if they make it, if you can't find 30 mm).
 
#14 ·
2 port USB charger
I thought $20 was a little steep for it (yes, I'm cheap), but Blue Sea seems to be a top notch brand, and most the reviews are stellar. I also didn't want to be plugging my X hundred dollar electronics into the cheapest thing I could find.
The mounting instructions call for a 30mm hole, but I didn't have a hole saw of that size. I ended up using a 1 1/4" hole saw and I wouldn't not want to go any bigger. 1 1/8" might be ideal (if they make it, if you can't find 30 mm).
Thanks for the info. I found that one on Amazon last night but wanted to see if you had found a cheaper one. The only other option I considered was to tear apart a cigar lighter dual port device, but mounting it would be a challenge. I've ordered the Blue Sea part.
 
#8 ·
What size polycarbonate rod did you use? I figured it might be easier to shape with a heat gun? Especially since you really just need the two bends for each end. Did it distort the material? (Became hazy or something)

Thanks
 
#9 ·
I used 1/4". (this is the exact one)
It was a bit more clear before I heated and formed it. I think I'll need to get some real plastic polish...I've tried aluminum polish and it didn't do anything (all I had on hand).
The 1/4" is the biggest that will squeeze into that opening, it's pretty tight! I can't recall how much I cut off of the 36" rod I got, you'd be better off measuring it again with a string than asking me, lol.
 
#11 ·
Yes! But it's just 5 plugs. The actual harness adapter is in the base of the passenger A pillar behind the trim. I'll look through other thread and see what photos I can find. I'll take the pics today or tomorrow, just need to solder connectors to my relay, when I go to install it I will snap some pics.
 
#12 ·
(I'm stealing these photos from another member's DIY)
This is the DIY that I roughly followed when rigging mine up.

Photo of the harness itself. There is a pair of plugs for the interior illumination kit, and a pair of plugs for the puddle lights. I think the 5th plug is just an extra ground? This is where I connected my home made harness. I just used "bullet" plugs I got from wal mart that fit into the connectors already there. Just use a multimeter to make sure you're on the right pair, the voltage should drop with the dimmer switch on the dash.


This is the image of the original plug in the passenger A pillar (this is before the adapter is added to allow for the LED kits)
 
#13 ·
Well I got the relays in, and it works! The interior illumination LEDs come on with the puddle lights. I had to use 2 relays since there isn't a common ground...
I am having one problem. I'm using the puddle light voltage to actuate the relays. But I'm guessing that the car uses PWM to dim them? The relays chatter like crazy when the puddle lights are dimming down...

Any electrical guys out there know an easy way to remedy this?


Relay harness


OEM LED harness, next to passenger footwell.



My LED inline fuse


OEM puddle light inline fuse
 
#15 ·
Yeah, I went with what I knew I could easily mount. I almost put it in the center console, but couldn't find a mounting point I liked, so I stuck in the cubby. Plenty of room back behind the plastic for it. I had the bright idea to just remove that cigarette light port that's already there, but they mount in 7/8" holes and this needs 1 1/4". Not enough material in that spot to widen the hole. I'm happy with where it is though.

I am having one problem. I'm using the puddle light voltage to actuate the relays. But I'm guessing that the car uses PWM to dim them? The relays chatter like crazy when the puddle lights are dimming down...

Any electrical guys out there know an easy way to remedy this?
Just wanted to isolate this so it's not lost in all the text around it.. I'd like to get the rattle snake out of my car, lol.
From what I've kind of read online it doesn't seem like an easy thing to do sadly. Might have to see if I can tap into the dome lights for the relay (and hope they aren't PWM too!)
 
#17 ·
Yes, the puddle lights fade and so do the dome. I was actually thinking about that last night when I got in the car, the domes fade too!
Hmmmmm, I'll ask some EE friends if there is an easy way to filter out PWM, I doubt it though. Might have to get a PWM compatible relay, or go to transistors if they make them big enough to handle the load. Never worked with them before.
 
#23 ·
That also looks like it will work. You'll end up with a relay that clicks on or off at some point in the middle of the dim cycle (wherever the output of the low-pass happens to cross the threshold voltage for the relay).

Reason I'm hesitant to suggest something like that is the possibility of backfeed. When the PWM signal goes high, the capacitor charges through the resistor. When the PWM signal goes low, the capacitor discharges. It discharges through the relay (if it's enough to turn it on), but it ALSO will discharge back through the resistor to the source of the PWM (the BCM). At the very least you need some isolation between the two to prevent that. Maybe just a diode is enough.

Using PWM to control a light is actually pretty nice. Instead of having to drop voltage as heat somewhere and drive a bulb with < 12V, you switch it on and off to get a nice clean dimming effect. it's how they designed the stock lights to work, why not take advantage of it? There's no harm in switching an LED on and off rapidly, and it will look really nice.

Not specific to Sub/OB, these new int lighting get their pos/neg events from the BCM (easily a $500 part). I can’t see exactly how you’re interfacing these relays, but it’s apparent they’re incompatible – remove them.
On my Mazda3, I tapped from the BCM connector for the dome to my footwell leds. I used those strip 3-head cool white leds (my dome/map is cool white), no other relays/pcb/devices in the mix, and the footwells behave exactly (remote/door/on) what the map/dome does.


The way you're wiring your lights involves drawing the extra power from the existing lighting circuit. The downsides to that are:
1). Extra power draw. The power you pull for those LEDs is coming off an existing circuit. If you pull more than it was designed to pull, it will hopefully just burn out a fuse, but could also burn out a wire. LEDs draw very little power, though, so you're probably ok.
2). Isolation. When you attach things to a car with a relay, there's a mechanical disconnect between your mods and the stock wiring. If you screw everything up royally, there's still a very low chance that it will ruin any stock components. When wired directly in, you don't get that isolation.

There are also some pro reasons. For some cars (like the subaru), the wiring is actually MEANT to power additional lighting. It has the extra power capability already ready to go. I would still add an extra fuse just to be sure, but it's reasonably safe. It's also certainly a much simpler and cleaner install that way.
 
#22 ·
Not specific to Sub/OB, these new int lighting get their pos/neg events from the BCM (easily a $500 part). I can’t see exactly how you’re interfacing these relays, but it’s apparent they’re incompatible – remove them.
On my Mazda3, I tapped from the BCM connector for the dome to my footwell leds. I used those strip 3-head cool white leds (my dome/map is cool white), no other relays/pcb/devices in the mix, and the footwells behave exactly (remote/door/on) what the map/dome does.
 
#25 ·
I've dropped the relays. I'll just run the interior lights off of the dedicated interior light circuit provided to me by subaru! Don't want to risk ruining the BCM just to have the red LEDs turn on with the domes/puddles. Maybe in the future I'll add some dedicated LEDs to the footwells that come on with the dome lights.
 
#26 ·
Polished up the diffuser and the light dispersal is much better. Not as good as the OEM one, but it looks good I think. If I had been more careful heating/molding the rod I think I could have polished it better. It's a pretty difficult shape to get crystal clear. Will post a picture shortly.

 
#28 ·
The 2010s came with the light diffuser ring already installed (lucky!). If you just want to add lights to the cup holder all you need to do is search the forums.
I searched with "cup holder illumination" and got this thread:

http://www.subaruoutback.org/forums/104-gen-4-2010-present/22006-cup-holder-illumination.html

Exactly what you're looking for. After tearing my dash area apart a couple times I can say that just doing that would probably take me 15 minutes. Make sure you get LEDs with the resistor already soldered on if you aren't able to solder. There are some links in my first post to superbrightLEDs, you can order exactly what you need.
 
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