DIY Electrical Work inside/outside your car!

AlienPrime

Well-Known Member
3,058
1,873
Sudbury, Ontario, Canada
Vehicle Model
Civic Si HFP
Body Style
2 door Coupe
Alright guys, so the electrical DIY's are countless, but i'd really like to take some time and really focus on a few basic aspects and do my best to help you guys all out in this regard.

First, there are two main sources to feed power from in our Civic's. First is the engine bay fuse box, second is the cabin fusebox. You can also feed power directly from the battery for sound systems and other high draw units like that but if you don't know what you're doing i suggest staying away from that.

All of my DIY's featured thus far have all been with the use of add-in-circuit fuse blocks.
Pictured below, this unit simply runs power into a fuse and into a single power feed. ANYTHING out of your fuse boxes will always supply you with 12v power.
add_a_circuit.jpg


For those of you familiar with residential electrical wiring, you will remember that everything must be grounded and returned in a neutral. In automotive wiring, this is not always the case, and in 80% of applications does not apply.
When it comes to automotive wiring, power is fed to a load, and then to ground to essentially complete the circuit. Majority of wiring projects will be run in a SINGLE LOAD SERIES circuit to avoid amperage loss. Some more complex wiring DIY's are run in parallel.

You can read on the hyper links so that i don't need to explain those.

I'm going to run through some very simple wiring diagrams to help you guys work on your own DIY's and any other project you'd like.

LEGEND:
Red Wire = Live/Power fed
Black Wire = Return/Ground
G = Ground
F/F = Feed
1/1 = Parallel branch # 1, 2, etc.
+ = Leading of switch. (Positive)
LED = Light Emitting Diode
C = Common (3 pole switching or multi relay)

1. POWERING A LIGHT/LED OR ANY LOAD
2IHVtPI.png


2. POWERING AN LED/LOAD - ILLUMINATED SWITCHED
No0uIax.png



3. Getting Multiple Switches on Single Feed
zjU8sio.png

**Use of ignition powered fuse slot required (Fuse #23 or #42)

4. Timed Relay controlled Variable Dimmed 24-SMD LED's in parallel to the current auto dome lights. A jumper is installed from Fuse #19 to your chosen feed. 20A is required. Relay must be NO (Normally Open Relay type)
wW8teGn.png

**Extra added terminals are timer type dependant. THR will dive + power once timer is triggered, hence LED for indication.
***This timer also has ability for RESET (set as push button type. As soon as reset terminal is grounded, unit is reset.


5. Splicing From the ambient light circuit (FUSE SLOT #35 @ 7.5A)
DbtwzOT.png


6. Using LED in signal housing with error correction (hyperflash)
d6TJFmE.png

7. Running Stock and HID with relays on separate source controller fogs
XlUvezh.png

10.
Running fog lights from battery through cabin switch:
NAeeM4V.png



Any other requests please PM me and i will add them up no matter how complex or simple. The list will continue.

For reference, here are fuse panel layouts.
FRONT ENGINE BAY FUSEBOX
zFunAvf.jpg

CABIN FUSE BOX
wca9O.sized.jpg


Enjoy!
-AlienPrime
 
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How about splicing off the ambient light switch/line in order to add more LEDs in various places?
yes that can be done as long as no load is before it. I will draw it right now... DONE

*************#4 DIAGRAM ADDED*************


will add #5 in a moment
 
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Added #5! :D

You can put as many as you'd like in #5 +3 LED, +4 LED etc, etc, just remember to change the 7.5A OEM fuse to a 15A+ to accommodate for increased amperage draw. :)
 
Can you explain what you mean by "no load before it"?
because before you splice, it is in series. In a series circuit, after a load, there is a voltage drop (therefore not being 12v anymore)

A load could be something like a light, LED, coffee maker, or horn whatever you put haha!

----------------------------------------

ADDED BEFORE/AFTER IMAGES to see changes :D
 
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Alright hotshot. Pop quiz.
Can you explain to the class in a diagram how this guy likely wired hybrid side mirrors to his Si? And if so, did his process potentially have any problems?
There are three gold stars up for grabs on this one.
 
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Doesn't look as though Mr. K24power07 wants to share his secret! haha well worry no more :D
I just so happen to know that the power mirror feed is more than sufficient to run the lights/reflectors for signaling inside :D (FUSE #14 in engine bay)

There are two wire that need to be run to that unit. You'd need to throw in a third wire for the mirror motorif you choose to get the JDM auto-folding mirrors (here)

Want me to draw a diagram? it may not help as much as you'd like but i can tell you what wires to tap into and where to run the power feed from. reality is, it's a OC swtich that runs off the command the signal stick gives. it is consistently powered and waiting for signal from the signal sticky thingy that you move up and down like a paddle :D
 
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