Running 4 gauge power wire

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Hardwarz

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Ok, I finally ran my 4g power wire through the firewall.

On the passenger side, I put a 3/4" hole between the AC/Heater fan and the the wiring harness. I put it as low as I could because the harness's molex plug is kinda big in the engine compartment. In the hole I used a Streetwire Firewall Bushing

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I ran the wire in the kick pannel and under the passenger's side door still. Under the door still on the front passenger's side is a conduit. The 4 gauge fit fine in there.

I had to unbolt the seatbelt. It take a T50 Torque bit to remove it. I ran the wire under the B Pillar cover and under the passenger's side back door still. From there it goes to the distribution block and amps.

Power is grabbed from the secondary battery. A fuse is put inline within 12" of the battery.
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The 4g power line was run in black split loom and goes along the firewall. On top of the fan shroud, you'll see 2 more runs of split loom (since they're dirty like the rest of the vehicle, you don't notice them as much.) One of those split looms has a 4g wire that connects to the battery isolator (which connects the 2nd battery to the electrical system). The other split loom contains the switched relay for the fog lights, trigger for the hood switch pin for the remote start and a power wire for the additional accessories. The power wire is fused within 12" of the battery and run through the grommet under the radiator overflow vessel.
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The power line was dropped down by the evaporator can and into a hole below and to the right of the Molex plug.
firewallclosenn4.jpg


Here's a close up of where the hole was drilled. Note the position of the Molex plug.
firewallcloservq6.jpg


Here's where the wire came into the vehicle. The round cover on the right is the AC/Heater fan.
insidekc8.jpg


I removed my glove box so I can add in extra fuse pannels. Each row is different. 1 row is constant +12V, one is NO +12V and the last one is +12 V NC. I use the NC to activate things like a blinking security LED when the truck is off.
gloveboxwz6.jpg


The 4g wire was run into the existing conduit that is located uner the door still. I had to remove the seatbelt (T50 torx bit) to get everything in place.
conduitpk2.jpg


The 4g wire was also run under the rear still and over to the amps.
rearvm4.jpg


With everything buttoned up, you can't even tell the 4ga wire is there.
donenl0.jpg


Hardwarz
 
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jnicks01

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Nice Job! Fortunately my wire was small enough to go through the stock grommet behind the coolant bottle. I've noticed that you ran your wires in the side plates along the doors. I started to do the same, but ran into a problem of rusty screws that liked to strip heads, so I thought to run to my local home depot and grab a 25' fish tape for 15 bucks. Using that, I could easily pull all my wires under the carpet from the split under the back seat. Took me about 10 minutes to pull everything from the front to rear. Just a future tip for anyone who may be interested.
 

Hardwarz

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Nice Job!

Thanks.

I started to do the same, but ran into a problem of rusty screws that liked to strip heads, so I thought to run to my local home depot and grab a 25' fish tape for 15 bucks. Using that, I could easily pull all my wires under the carpet from the split under the back seat. Took me about 10 minutes to pull everything from the front to rear. Just a future tip for anyone who may be interested.

Damnit! Why didn't I think of that. I have $1000s in tools and 2 different fish tapes! Now I might go back and re-run it correctly. (but probably not, I'm lazy. lol)

Oh... 1 screw was rusted. I'm going to replace them with SS screws all the way around. I think the MFG should always put SS screws there!

Hardwarz
 

YukonMud

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I much prefer running it under the sil, imo it looks much cleaner and easier to modify in the future...because once you get your system up and running for some months later you're going to get the stereo bug and want to run a larger wire and more watts :)
 

qlc1964

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sinse my amp rack is right behind the rear seat i had to take the whole thing out to run
my wires. and i would move the wire from where you got it along the door seal.

and uuum whats up with dirty engine
basically under your hood:nonod:
 

Class_D

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Nice work on the running of the wires to the back, good job!
 

Hardwarz

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and uuum whats up with dirty engine
basically under your hood:nonod:

I go target shooting a lot. To get to one of the spots where we shoot, my friend's land has a quad runner trail that we have to drive up using 4x4x (My Tahoe, a Toyota Pick up Truck, etc.)

Sometimes, the path is VERY muddy and kicks up EVERWHERE! The path is also on the side of a large hill and there's zero clearance for error. It's fun!!!!

This is also the reason i snapped a leaf on my rear spring and the link between the frame and the tortion bar crossmember.

Hardwarz
 

TangibleGhost

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dumb question, kinda late too

I removed my glove box so I can add in extra fuse pannels. Each row is different. 1 row is constant +12V, one is NO +12V and the last one is +12 V NC. I use the NC to activate things like a blinking security LED when the truck is off

I'm a bit new to electronics lingo. What did you mean with the 12v NC and NO?
 

Hardwarz

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NO = Normally Open
NC = Normally Closed

You'll refer to NO or NC when there is no power to the circuit, therefore if there is no power to the trigger of the relay,:
Open more or less means off (Open circuit, a break in the circuit)
Closed more or less means on (Closed circuit, flow of electrons goes through the circuit)

Good relays have the following terminals

30 common
85 Trigger (coil)
86 Trigger (coil)
87 NO
88 NC

The great thing about a relay is that you can use it differnt ways.

The 2 trigger terminals needs a +12V and a ground. Depending on where you're using it the trigger may be ground or may be +12V. (Example: On most Japaneese vehicles, the door pins are grounded when the doors are open. Therefore, you supply the trigger +12V and connect it to the door pin. When the door is open, the +12V goes from the power source, through the coil to the ground, on most domestic vehicles the door pins are +12V, you connect the +12 to a trigger and then ground the other side. When the doors are open the relay's trigger is activated.)

Think of the relay as nothing more than a switch or diverter.

If you supply the common +12V you get +12V out of 87 or 87a. If you supply a ground to the common, you get ground out of 87 or 87a. The trigger tells the relay which terminal to switch to. If the relay is not activated by a trigger, power is transfered from the common to the 87a. Once it's triggered, power is removed from 87a and moved to 87.

Note, you don't have to use 87a. You can just use 87 or 87a individually.

Now, why would you want to use 87a?

I have a relay setup in my vehicle. When the vehicle is off, it sends power to 87a. This power is used to activate things that need power only when the vehicle is off. Security LEDs, security motion sensors, etc. These do not need power when the vehicle is on and running.

Another reason to hook up a relay is to keep power lines short. If you have large flood lights that use 12g wire and 30 amps, you can run a fused 30 amp line from the battery to the common (30) on the relay. That wire will then go from terminal 87 to the lights. Ground terminal 85. Run a fused +12V from inside the cab, to a switch (Fuse can be small, like 3 amps.) From the switch to terminal 86 on the relay. All the heavy wiring is short and where it needs to be, not run into the vehicle to the switch and back out. Hooking up a 2nd relay can make the lights only come on when the vehicle is running. Great when you don't want to accidently leave a light on.

I hope this helps.

Hardwarz
 
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YukonMud

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wow, great post Hardwarz. I was just trying to figure out how to put a relay in my truck...I think this info will help out a lot.
 

TangibleGhost

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Wow, Thanks a lot. Extremely informative. Now I just need to find some stuff to run off of them so I can tinker with 'em.
 

YukonMud

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I am running some fan's for my amplifier and thinking about adding some neon behind my amp.
 

Hardwarz

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I am running some fan's for my amplifier and thinking about adding some neon behind my amp.

You can use the remote wire from the head unit as a trigger for the relay. From there you can connect a fused line to the neons and fans. Doing it that way, you're not going to drawing much current from the remote wire on the head unit. Also, neons and fans will only come on when the head unit is on.

Personally, I like having a switch leading to the subwoofer amp. The ability to press the switch and kill the subs is a great thing for me. When I spot police, I can kill the subs. When I get closer than 3-4 blocks from the house, I kill the subs.

Hardwarz
 
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