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To read the original full thread and post questions/comments on this topic, please go to

I decided to make up a “How-To” install roof rack lights wiring and switch and gauge installation. I have noticed that there are many threads with a little bit of everything, I wanted to have one place for everything.

This will be done in many parts as the work is completed. I will add pictures with a list of required tools and supplies that will also be needed to accomplish the work in a very professional type of wiring installation. I will also go into some detail of the reasons of why I picked certain items than others. This may help you decided on what you want to accomplish.

The first thing you need to do is establish where everything is going to go. Another words, you need to layout in your mind where your switches and the types that you want to use will be in the interior of the vehicle. It is also very important to layout any future items that you may want to add also.

I decided to use the small panel located along the driver’s side under the vent. I have seen other post that there isn’t enough room there. I have found after removing the panel, there is plenty of room for what I want to do.

I have the following lights on the vehicle that will need switches.
  • PIAA Driving Lights (Bumper) – 1 Set
  • IPF Driving Lights (Front Grill) – 1 Set
  • IPF Spot Lights (Front Roof Rack) – 2 Sets
  • Flood Lights (Rear Roof Rack) – 1 Set
  • Future VIAIR Air Compressor w/ Storage Tanks (Sleep/Storage Box) – Switch & Gauge
As you can see I have thought out all the items present and future that will be added to the vehicle. Now with my list, I see I have a lot of switches plus a gauge to add.

I first laid them out like I stated above where I wanted to have the switches located. I bought a couple of the OME switches for the vehicle with harnesses from one of the forum venders about a year ago. I noticed I do have room in the center console to add my switches in there, but decided against it for a couple of reasons. One is, it’s very easy to “bump” and turn on one of the switches in that location. I would not want to be running around in the daytime with my roof lights all on. I wanted something of a safety feature incorporated in the layout and design.

I decided to go with the racing type toggle switches that incorporate a safety cover over the top of the switches. Most of you have seen the type of switch I’m talking about, it has a flip up cover on them. When you turn them on, the cover has to be lifted and when turning them off, just push the cover down which shuts off the lights. These types of switches are also used in the aircraft industry.

I decided to mount four of them along the bottom portion of the panel and then add an Air gauge with switch above them.

Before writing this up I had already mounted the four switches as you can see in the picture.

To remove the panel, just grasp from the bottom portion of it, and pull outwards. This will unseat the tabs that hold the bottom portion of it. DO not pull any harder than is necessary, it will only pull out about an inch then grasp the top portion around the vent. Pull outwards straight out. The whole panel will pop right out.

As you can see, there is plenty of room to mount switches behind this panel.

Next after removing the panel, I took it back to my work shop. I first placed masking tape over the area I will be working on so as not to damage any part of the front panel. This also gives me a place to mark my locations for drilling.

I noticed that where I want to mount my switch for my Air Compressor there is a tab located in the way. After examining the rear of the panel carefully, I decided I can get by without this one tab that holds the panel on to the dash. I first drilled a hole of where the switch will go.

Then turning the panel over I used a Dremel tool to remove the rest of the tab on back, this allowed for a flat surface to mount my switch.

I next drilled out the gauge hole and used a Dremel tool to sand away a little more material away so the gauge would fit perfectly.

I than test fitted the gauge and mounted the Air Gauge switch on to the panel.

Sorry for the blurry pics in some of these, I didn’t realize they were this bad when I took them. But I think you can get the idea.

I next had to shorten the gauge holding bracket on the rear of the gauge. It is way to long for this application. I’m already a little tight on space back there. I used a marker to mark the location where I wanted to remove excess material from the bracket, I then cut it off with the Dremel tool again at an angle since I’m using an angle gauge mount on the front.

Now it’s time to test fit in the dash to make sure anymore of the inside plastic needs to be removed. I also went ahead and wired back up two of the lights I had already had hooked up to the switches. These were my PIAA’s and the two IPF’s on the front bumper.

I installed the panel back in the dash and everything fit perfect, here is a couple of pics of the finished product.

Part two of this install will be installing all the roof lights and wiring along with my Lowrance BAJA 540C GPS antenna which by the way I have to make a mount for on the rack. I will also go into detail listing all the tools and electrical connections that you will need for the install. :)

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6,484 Posts
Re: HOW-TO Install Roof Rack Lights, Wiring & Gauge Installation w/ Pics

Part 2 - Installation of the Roof Light Wiring

The following pic is the tools and equipment that you will need when doing the lighting for this MOD.

  • Wiring loom
  • Electrical Tape
  • Multimeter
  • Circuit Tester
  • Assorted Wiring Connections
  • Carflex Electrical Fitting
  • Carflex Electrical Fitting “Water Resistant”
  • Myers Hub “Water Tight” Electrical Connector
  • Greenlee ½” Knockout Cutter ($23.00) Or a Uni-Bit
  • Rubber Grommets
  • Liquid Electrical Tape
  • Assorted size Heat Shrink Wire Wrap
  • Wire Snips
  • Electrical Pliers
  • Wiring harness from Light manufacturer
  • Permanent Marker
  • Assorted Hole Saws
  • Needle Nose Pliers
  • Assorted Tie Wraps
  • Tape Measure (Not Shown)
I want to talk about a couple of the above items, number 6, 7, 8 & 9. There are two different types of electrical fittings that you can buy. The first is what is called a “Carflex Fitting. These are “Water Resistant” not Water PROOF. They are made out of a polymer that will expand and contract. I myself didn’t know any better and bout the two that you see in the picture above. Then I spoke with my father who has been an Electrical Contractor for many years in the Industrial area. He said that most electricians don’t use the “Carflex connectors due to they leak after about 6 months to a year. He stated that most use what is called a Myers Hub, which is a true “Water Tight” connection.

Armed now with some very useful information, I decided not to use the connections I had bought. My dad sent me a Myers Hub he had along with a pretty cool little tool to make the whole in the roof with. If you do plan on using the Carflex connection or have already, just make sure to periodically check that you still have a good seal once or twice a year.

The number 9 in the list is called a “Knockout Cutter” and is used to make a nice clean hole in the material that you want to make a hole in. My father said you have to be careful when using a step drill bit or a hole saw, it has a tendency to “Grab” the metal and want to twist the drill out of your hands or damage the area around where you are making the hole. This is why he said the Knockout Cutter is used to avoid that type of situation. It makes a nice clean hole.

I’m going to start off with the rear flood lights in my case. I have a GOBI Ranger rack which came pre-wired for the rear lights. As you can see in the pic the end of the wiring is tied up in a little plastic bag, which also has (2) wire connectors too.

I first slipped on a couple of heat shrink tubing over the wires.

I then used two wire connectors to tie the wires together. As you can see, I kept black with black and white with Red. Black will be my ground wire. White on the other end will be my Hot.

I then slipped the heat shrink tubing over the connections and used a lighter to shrink the tube over the connections to make a watertight fit.

Then using a wire loom to incase the wires to make a clean professional appearance.

I then taped around the wire loom to keep any unwanted moisture out.

I then using Wire Tie wraps attached the wiring harness to the sides of the rack.

I then repeated the same process for the light on the other side in the rear of the rack. Here is a pick of the finished wiring installation.

I’m now done with the two floodlights in the rear. I will now move to the front of the rack to begin wiring the (4) main spots and the rear floods into one harness.

Now before I can begin running the rest of the wiring, I need to make a new GPS antenna mount for the rack. I used some sheet metal I had laying around in my shop and made a small mount for the antenna, I then painted it black to match the rest of the rack.

I next had to figure out where I wanted all the wires to come through the roof at. I know some make the hole closer to one side or another, this helps keeping the wiring closer to the A-Pillar. I myself decided to come through in the middle as close as I could get to the GPS antennae location, here is why. I have the Lowrance BAJA 540c GPS, the antenna has a small cable that comes off the antenna, which has a small fitting at the end. It doesn’t have much room to play with, I will have to cut the plug connection off and then splice it inside the roof-line. I used some masking tape and placed in the general area where I wanted the hole to go through at. I then placed the Myers Hub in the location and made sure my antenna mount wound not interfere, once installed.

I then drilled a hole for the cutter.

I then inserted the “Knockout Cutter“ in the hole.

I then went to the inside of the vehicle and removed the visors, GPS mount (you will need to remover your rear view mirror) along with the grab handles, then pull from the top of the a-pillar I removed the covers and the head liner was able to come down enough for me to work under the roof line.

I then installed the “Cutter” end of the knockout cutter under the roof.

Using a wrench I began to tighten the cutter down applying pressure.

Once the cutter went through, I was left with a nice clean hole in the roof to fit my “Myers Hub” watertight connection in.

I then used touch-up paint to protect the edges of the exposed metal around the hole.

I next inserted the Myers Hub inside the hole and the other end on the inside using a wrench to tighten it down nice and tight for a good Water Tight Seal.

I next used some Teflon tape for my 90 degree fitting for the hub penetration.

I decided to use some very large Heat Shrink Tubing I found at Home Depot, it’s used to make underground splices of cable. It fit perfect over my 90 along the threaded part. Once I have my wiring harness all made up and then inserted into the connection, I’ll use some heat to make a nice solid watertight seal.

Emeritus Moderator
6,484 Posts
Re: HOW-TO Install Roof Rack Lights, Wiring & Gauge Installation w/ Pics

Part 2 Continued:

It was time to make up the rest of the wiring harness. I started by finishing up the other end of the floodlights that are in the rear. Again, GOBI has already ran the wiring out in the front of the rack to make my connections that more cleaner in appearance. Again just like in the rear, I placed some heat shrink tubing then made up my spices using a standard wiring connections.

I then shrink wrapped the wiring and encased it in some “LARGE Wire loom, the reason for this is I will be adding a lot more wires into the same loom along the way.

I next installed the manufacturers wiring harness onto the lights.

I then cut off the wiring harness a few inches from the plug for the relay.

I then stripped off the plastic sleeve protector from the harness.

I then started wrapping the exposed wiring harness starting from the outside one into the finished rear floods in the Large wire loom. This incased all the wires into the same area and loom. Then, using electrical tape I taped the loom up as I went.

Once I finished all the lights, I had (2) looms that came together in the middle of the roof where my roof penetration is located. I also spliced together both the rear flood light wires into one hot and one ground.

I then taped the whole harness up to make it easier to come through the small fitting into the roof-line along with helping to protect the wires. I then pulled the harness into the interior.

I next had to fit my GPS antenna and due some test fitting due to the short antenna cable.

I then installed the antenna bracket along with using heat to shrink up the tubing around the wiring harness, then encased it electrical tape. I then used tie wraps to keep all the neat on top.

All the outside wiring is now complete and water tight. The next part will include all the inside wiring up to the switches, stay tuned. :)

Emeritus Moderator
6,484 Posts
Re: HOW-TO Install Roof Rack Lights, Wiring & Gauge Installation w/ Pics Part 1 & 2

Part 3

****FIRST disconnect the Negative Terminal on your battery before doing any Electrical work.***

Here are the items laid out before finishing up the wiring install.

I’m using LandCruiserSteve's idea of splitting the Fuse box into (2) sections and running (2) 40amp Breakers and (2) 40amp Relays. By doing this all my electrical will have power from the Aux stock fuse box inside the cab. I too will be using an Add-A-Fuse for the power to the relays. He made a great diagram of the wiring here is a link:

I decided to use 8ga wire for my main power and ground connections. I am using more than I need at the moment, this is due to adding a duel battery setup under the hood in the near future. By keeping this in mind, I am making my main leads “longer” to accommodate the extra battery when installed.

I taped the two Positive lead wires every few inches with Elec tape to keep them together, then wrapped them up in a wiring loom and tapped it up over top of the loop keeping everything neat in appearance.

I decided to make a panel for my 40 amp breakers and relays. I took a piece of steel I had in my shop, approx 9” long, then held it in place where I wanted the panel to go.

I then tested the fit with everything mounted on the steel.

I then removed everything and painted it with a couple of coats of primer, then painted it flat black

I mounted my breakers and relays back on the panel.

I then mounted the panel inside the engine bay.

I hooked up all my wires, running the main lead (power) into the breakers, then back out with a short jumper to the relays, then back out of the relay into the inside of the drivers side of the vehicle under the dash.

The (2) clear are the main power to the fuse box, the (2) black are my grounds and the (1) red wire is my main power to the add-a-fuse for power to the relays under the hood which will provide power to all my electronics.

All the main leads made up under the hood, finished.

I next pulled my wiring harness into the drivers side A pillar.

I ran the wiring down under the dash and labeled all my connections.

I then removed my switch panel, and ran all my wiring down under the dash where everything would be connected to the fuse box.

I then removed the front cover and the rear of my Blue Sea fuse box.

I removed the inner power bars.

I cut the top and lower power block bar in half, to make (2) separate fuse blocks.

I then made a small jumper from the bottom half to the top half. Then screwed the back of the plate back on. Now I can hook power to the top and bottom of the fuse block.

I already had a 6 fuse Blue Sea box, I did the reverse on this and used it to mount all my grounds to it. I made a jumper to all the inner terminals to make everything connected. I can now hook up both incoming grounds to the top and bottom of the box.

I mounted my new 12 position fuse box to my existing mount I made before for the smaller one, it fit perfect.

I then was ready to hook up the main power to the relays with my add-a-fuse. I also was able to use an unused position in the stock fuse box, the middle row 5th from the left. Using my millimeter I was able to see it is only hot when the key is turned to the on position. Now all my electronics will go off when I turn the key off. (no dead batteries for me).

Next the last finishing touch was to hook up the main power and negative terminals to the battery, that’s it.
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