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Premium Member
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Discussion Starter · #1 · (Edited)
Hello Gang,
So I decided to install Under Hood LED Strips.
I was inspired by Stinger with his DDM-Works installation.

Materials Needed:
- Black Tape (To cover wires and protect)
- Mercury Switch* (To turn on the LED's automatically when the Hood is open)
- Wire (I used spare speaker wire I had hanging around - 2 strands Pos / Neg)
- Solder + Torch (I soldered all connections but 3M Clips could have been used)
- Shrink Wrap
- Add-A-Fuse Adapter
- Small & Medium Flat screwdriver (to remove push pins that hold the fire tarp under hood)
- Wire cutters, Strippers
- LED Strips (I had 2 hanging around)
- Torx Set 10mm (to remove the Left Rain Pan)
- Drill with Bit

- LED Strip: (free for me - I had this hanging around but prices vary ~ $10)
- Add-A-Fuse Adapter $12
- Mercury Switch $6

* (where I got my Switch - took 2 days to receive)

Time: About 4 hours, after figuring out the logistics.
The longest time was soldering the cables and playing around the wire to make sure they were all taped up and protected (inside the hood frame and out).

To start I needed to decide where to find power.
I wanted an unswitch circuit so the ignition did not need to be on for this to work. Thankfully the Under hood Fuse Box had plenty of Fuses that satisfied that requirement. The bank of fuses nearest the firewall (in the box) were most all unswitched. I simple test with a volt meter showed 12V (DC) across multiple fuses. (make sure you select < 10 AMP fuse, since my ATA Add-A-Fuse is rated at 10A only.)

I elect to punch a hole near the back of the box to keep things as "incognito" as possible. I used a torch heated wire to punch a starter hole, then drilled a 1/8" hole for the wire exit. The wall of the box is not flat here so a starter hole is paramount to be successful in drilling a hole. I was lucky to find a plug for this hole, as this box seems to be pretty well sealed-up from water ingress & I wanted to maintain that aspect. I used the rubber foot of an OLD Coffee maker and drilled a small hole through it, worked perfectly.

I then needed to find a location for the LED Strips. I chose the top and bottom of the black fire tarp on the underside of the hood. Passing the wire in back of this would prove difficult, if I did not partially remove the tarp. I removed the 2 right rows of push pins and "gently" pulled them out. One must be Extremely careful with these as they are brittle and can easily be broken. A screw driver is not the optimal tool but hey that's what I had. I ended up only partially breaking one of the 8 or so I removed. Once the driver side unhooked, I easily affixed the LED Strips (Mine had 3M 2-way tape on them) at the proper location and ran the wires, calculating enough slack for the run to end up at the fuse box and the engine ground.

Now for the Mercury Switch. I used the right most top screw of the Driver Side Rain Tray as anchor the mercury switch. (that way no metal contact with the car body was needed) I completely removed the tray (5 screws) and created a wire pathway in the ribbing of the tray using a small drill bit. I glued a small back plastic tube to hide the wire path from the sensor. I then reassembled the tray in place, with the sensor in place.

I soldered together the wires from the top strip and bottom strip and ran the remainder of the 2 strand wire through the bottom hole in the hood. I then re-anchored the tarp in place.
I ran the wires from the mercury switch in-line to one of the 2 wire leads (soldered) which exited the bottom right hole of the hood next to the hinge. From here I taped (or covered) the wire and ran it the same way the passenger (left) hinge wiring is done, with a tie-wrap. A wire harness was also added and attached to the pin plug holding the back rubber Strip, right next to the hinge. (I wanted to make sure the wrapped wire would not get pinched when the hood closed. At this junction I split the pair Red going to the fuse box and black going to ground near the front of the engine bay. The Wire being wrapped in Black Tape all along. This make it look OEM.
See diagram to be better able to follow the wiring path.

The switch works great.
I doubt very much that I will have the LED's turn on during hard acceleration. Its almost as if the bulb is made in such a way as to avoid this. Take a look at the angle for them to turn on. I could have bent the retaining arm to make the angle at which the LED's turn on greater but so far I do not think it is necessary.

See video:

Let me know if you need clarification
Thx Stinger, for the inspiration

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