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How to Install Interior Car Lights
(Neon & LED)

My guess is that you've got all the components of your LED or Neon interior car lights in front of you and you're now a bit confused as to what you should be doing next... am i right? And now you're asking yourself - "where the heck do all these bits go?" Then fear not, save the gray hairs for a later date, cause you just landed on the right page to help you find out all the "whys" & "Hows" of this type of installation - which i should mention, has been designed with the "Novice" in mind.

The instruction page below is broken-up into TWO PARTS. Each part focuses on a separate way of accessing the 12v power for your interior or exterior car lighting accessories.

Part 1) The First place that you would naturally get power from, is DIRECTLY from the car battery. This set-up is the Number 1, HIGHLY RECOMMENDED, and EASIEST method of all.

Part 2) The second place to get power for your LED's and Neons would be from a live 12v wire located under the dash area. This method we *DO NOT RECOMMEND* and the installation is somewhat more complicated. However, we have many customers requesting how to install interior car lights when the ignition is turned on, so we decided to help you with this type of set-up anyway.
Your most likely wondering, why is power from under the dash NOT a good idea? Well basically, it can cause car wires to overheat and burn out, should you happen to wire up your lights the wrong way, or "tap" into the wrong wire to access power, which happens too often. But we figured, if there are people out there that want their power from under the dash, so their lights come on when the ignition is turned on, then we may as well show you how to install them the correct way, but it is labeled, "ENTER AT OWN RISK".

Another Word of Caution on how to install interior car lights, BE WARNED, if you do obtain a 12V power supply for your LED/Neons from one of the wires under the dash, be sure that it's not the headlight wires, because you cannot turn the neons or LED's off while driving at night, (unless you have an in-line switch) and be twice as sure that the wire your tapping into has 12volts of power running through it by using a voltage meter and circuit tester, and be tripply sure to install a fuse on the power wire going to your LED/Neons.
But it is still highly advised to access your power supply from the car battery and NOT from under the dash. However, if this type installation is done correctly, you should have no problems, it's been done many times before without any drama, but we'll leave the "risk-taking" up to you, we'll just supply the guide, but it is by NO MEANS meant to be taken as a solid "blue-print", because cars, people and situations differ.

Remember also, with some later model cars and messing around with wires under the dash board could accidentally activate the air bags, so don't say we did'nt warn you!

How to Install Interior Car Lights via the car battery - Step 1

The tools your going to need to do this installation. You'll need...

A toggle switch (to control tubes independently)
Soldering gun and solder
Electrical tap or heat shrink tubing
Flat head screw driver
Star head screw driver (should you need to remove any interior panels)
And any other tools that are mentioned in the instructions that come with the led/neon kit that you have purchased.
These instructions have been designed with the "Novice" in mind, so if thats you, then please read-on carfully - its really not that hard.
How to Install Interior Car Lights via the car battery - Step 2
As a rule, before doing *Any* electrical work on your vehicle, always disconnect the battery before starting (be aware that in later model cars, disconnecting the battery can disrupt the cars electronic systems). Do this by disconnecting the negative battery cable and laying it to one side so its not touching any metel parts. It's also wise to have your vehicles service manual handy for information about the specifics of the electrical system on your vehicle should you need it, but you should not.
Ok, lets get started. In this installation we'll be showing you how to install interior car lights using ONE neon tube as an example. What you'll need to do first is find where you want to mount the tube and keep its location in mind while doing the wiring part of the installation, so you can allow for the correct lengths of the wires.
For the interior, the best place to mount the tube is under the dash just above where the feet go, but high enough so as not to kick the tube or damage it. They also look very effective mounted under the front seats and towards the "back area" of the seats so the light shines into the rear part of the car floor.
The picture below shows the neon tube mounted under the drivers side dash.

How to Install Interior Car Lights via the car battery - Step 3
In this set-up, you'll be running both the main power wire (with in-line fuse attached) and earth wire from your light kits directly to the car battery. This Method is HIGHLY recommended for one or two car lighting accessories, and is the easiest way to do it, but after two or more light kits are installed this way, your car wiring system coming from the battery will start getting real messy. So to install many accessories via the car battery, you going to need some kind of fuse protected distribution control panel that all your lights will plug into, and that you have easy access to. This is the coolest, easiest and "most-hassle-free-way" of hooking up and controlling multiple lights.
Such a distribution control panel that you can plug all your lights into is now available, the LED Distribution Control Panel
Ok, moving on...
To operate your lights manually, your going to need a switch located near you, so, you'll need to buy a simple "2way toggle" switch (or use the switch that may have came with your neon/led tube kit) from your nearest auto accessories store. This switch will be inserted into (in-line with) the main power wire that supplies the kit with 12Volt power.
You simply cut this power wire for the kit (making sure you have positioned "ALL" components in their locations and are sure the wires are long enough) and then join each end of the power wires you just cut into each side of the toggle switch. As shown below. This will allow you to switch the tube on & off independently from a direct power source. You can mount this switch in any "easy-to-get-to" location on your dash if you wish.
see picture below of the example switch "in-line" with the neon tube's power supply...

How to Install Interior Car Lights via the car battery - Step 4
Now that you have joined the switch into the power wire of the light kit, you'll now need to run a "fuse-protected" power wire from the battery going to the switch. The fuse should be no more then 18 inches away from the positive terminal on the battery. You may need to solder the fuse to the power wire for your lights, or the fuse may have already come complete in the kit, however, if you need to solder any wires together, be sure to use heat shrink to cover your soldered connection (put heat shrink on first BEFORE you solder wires together). Once you have soldered the wires together, then "smear" a small amount of silicone over the joint, then slid your heat shrink over the joint and "heat-up" with a cigarette lighter untill the heat shrink tubing "shrinks tight" around the soldered joint.
You can see this "fuse-protected" power wire below...

You will need to run this power wire through one of the "existing holes" in the firewall of your car to reach the battery. This is the wall that separates the interior of the car from the engine compartment. If you do go drilling holes in the firewall to pass through wires, be sure to insert a rubber grommet to prevent the metal rubbing the wires bare.
Important: For any vehicle project that involves drilling holes into the body, its a good thing to first check where you're going to drill the holes to be certain you won't pierce or damage any crucial parts such as brake lines, fuel lines and electrical lines, etc, that would be a real shame!
Open the hood of the car to find these "existing holes" and also look from inside your car by positioning your head anywhere under the dash so you can "clearly" see where exactly the existing wires are going, what holes are available and how they go through the firewall into the engine compartment.

How to Install Interior Car Lights via the car battery - Step 5
To complete the "electrical circuit" - you'll now just need to attach the earth wire from your led/neon tubes to the negative ground earth of the chassis. You can do this in TWO WAYS...
1) Attach it anywhere where there is bare steel under the dash is always a good earth connection, even if you find a screw under the dash that is already screwed into bare steel that is holding another wire in place as an earth, you can use this too as an earth location. Or...
2) You can run the earth wire along the same path as the power wire going straight to the "negative" side of the car battery, this is most likely the easiest and surest way of do it.
How to Install Interior Car Lights via the car battery - Step 6
After your "power" & "earth" connections are complete, your led/neon lights should now work through the switch you installed. If they appear dull, not real bright, or flicker on & off, then be sure to check that you have made GOOD earth and POWER connections.
If by chance something stops working on your car while you are doing this installation, just check the fuses in your car, as you may have blown one. But this should not happen because you are accessing 12volts of power directly from the car battery on it's own circuit. Fuses only cost about 50cents each and you get them from car accessory stores, just show them the one you have blown, and they will have one there to replace it. Just be careful not to "short-out" or "cross" any wires, and you should be fine.
How to Install Interior Car Lights via the car battery - Step 7
That's it, your all done - now all you have to do is put any plastic panels back into place that you may have torn off, and then head out to show your friends what a great look you've just created on your car.
If these instructions all seem a little "over-whelming" - then your best bet is to print out these instructions and read them through a few times to familiarise yourself with what you need to do. Then when your ready, have these instructions with you while your installing the LED or Neon interior car lights into your car.
And if your still un-comfortable with this installation - and feel that you cannot do it, then your going to need to contact a professional who can. There are a growing number of car accessory installers that provide these kinds of services, just ring around at a few places to find out who will do this installation for you.
Good luck and Enjoy!

How to Install Interior Car Lights using 12v power from under dash - Step 1

Don't do it unless you are REAL familiar with the Challenger computer system - it is resistance driven and wiring using under-dash power source can cause everything from computer crashes to FIRES!!!
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