DIY HID Flashlight for Your Car/truck




Once or twice a year, my family and I go camping with some friends. Usually we show up at night and have to set up camp in the dark. This can get pretty frustrating using just regular flashlights and using car headlights is difficult to move around. So I came up with a way to make a HID flashlight that has become very useful for not only camping but is a great tool to keep in the car in case of emergencies (flat tires, etc).

Step 1: Materials


- Big flashlight that uses a 6V H3 Bulb
- 25 ft extension cord
- Cigarette lighter plug (comes with flashlight)
- H3 HID bulb
- HID Ballast
- 1 Large Zip Tie
- 1 Small Zip Tie
- Soldering iron

The flashlight that I used has an adjustable stand and a swivel handle which makes it very useful.

Step 2: Removing the Original Bulb

The first step is to open up the flash light, this is done by twisting off the black ring around the bulb/reflector. Once you have that open, you need to disconnect the current bulb by disconnecting one spade connector (White wire) and unscrewing the black wire.

You should wind up with this:

Step 3: Install the New Bulb

Remove the bulb by popping out the wire holder. Then take you new HID bulb and put in place and replace the wire holder bending it around the new bulb.

Step 4: Remove the Insides

The next step is to remove all the inside pieces from the flashlight.
Unscrew the switch, charging port, battery holder and remove all the pieces. Also remove the rubber cover for the charging power.

This step will leave you with some handy parts for other projects, namely the battery and charging port.

Step 5: Power Switch

Take the switch and cut one wire so you are left with this:

Step 6: Putting in the Power Cord

Cut one end of the power cord and strip back a few inches. There should be three wires inside, you only need two, I used white and black. Run this through the hole where the charging port was.

Step 7: Make the Connections

Put a zip tie on the power cord so it does not slip back out. Connect the spade connector from the harness connected to the HID bulb to the power switch and the other red wire to the white wire on the power cord. Cut the black connector from the HID bulb harness and connect it to the black wire on the power cord. Cover with electrical tape. (Make sure you are not cutting the wires connected to the bulb itself, just the ones on the other harness to plug into the ballast.)

As per a comment, it would be a good idea to put in a fuse for safety reasons. Get an inline fuse from an auto parts store and wire it in between the white wire and the switch in this step. (Where the white and red wire are connected in the picture.)

A fuse like one of the two pictures will work, around 10-15 amps.

Step 8: Putting the Body Back Together

Make all the connections from the bulb to the ballast. Place the ballast inside the flashlight where the battery was and brace on either side with some cardboard so it doesn't rattle around. Reinstall the switch where it was originally. Then you can carefully put all the wires into the body of the flashlight and put the cover back on.

Step 9: Powering the Flashlight

Take the cigarette plug that came with the flashlight and take it apart, removing the wiring and rubber piece at the base. (Remember where the wires were soldered to)

Cut off and strip the other end of power cord as shown. (The black wire shorter than the white)

Step 10: Cigarette Lighter Plug

Using a knife, run it around the opening at the base of the cigarette plug where the wires run in until it is just big enough for the power cord to fit in. Put a small zip tie on the cord so it does not slip back out. Solder the black wire to the center of the silver piece of the cigarette lighter and the white wire to the top of the cigarette wire, as the original wires were soldered.

Step 11: DONE!

Put the cigarette lighter plug back together and you're all done!

Test in your car or off a suitable 12V power source.



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    14 Discussions


    3 years ago

    Recently I bought this Powerful Mini Flashlight, looks great and can also adjust the focus range for different usage, Strobe light option for flashing Emergency Signal. Use this code "PD10"and save 10%.


    8 years ago on Step 3

    i hope you were VERY careful to not let that bulb touch your fingers or anything. some reason, this can shorten the bulbs life.

    6 replies

    Reply 8 years ago on Step 3

    Yes, I did not touch the bulb. If you need to touch HID bulbs or accidentally touch them, its best to clean them off with a clean cloth afterwards, from what I understand, the oils from your finger can shorten the life of the bulbs causing them to fail early.


    Reply 8 years ago on Step 3

    do you know why, my theory is that while the bulb is hot, and the dirt (oil, proteins, dead skin cells etc etc etc) will vaporize on the bulb and weaken the super fragile glass.

    i have been told that grease from fingers increases the temperature inside the bulb because it blocks heat from transferring out of the bulb. Bulb filaments are very sensitive to excess heat and the more hotter inside, shorter the lifespan. The difference is small but it still counts. Also, wiping with cloth alone is not enough. Brake parts cleaner or very pure alcohol is best in cleaning the bulb if touched by accident. This knowledge is based on me working many years on car parts sales and mechanic.


    Reply 7 years ago on Step 3

    Both HID and Halogen bulbs are not infact traditional glass (it can't handle the high temperatures). The bulb is actually quartz. The reason touching the bulb with your skin will cause them to fail is because the oils will cause the heat to build up and fisures will form in the quartz allowing the gas inside to seep out and air to seep in.

    Sort of like the way oil from leftover food melts through a styrofoam container when in the microwave. if the oil was not there the container would be perfectly safe.


    Reply 7 years ago on Step 3

    I know the bulb is quartz. So that's why the bulb goes bad when touched...


    Reply 8 years ago on Introduction

    where did you get the flashlight from? is it one of those "dollar store" type of 6V lantern? what about the battery?


    Reply 8 years ago on Introduction

    It was a 6V H3 bulb that was in the flashlight, making it an easy swap with no need to modify the bulb housing.


    10 years ago on Introduction

    yes I've seen hid light kits somewhere for like 20 bucks


    10 years ago on Introduction

    Thanks for the comment, I had thought of it and completely forgot when I made this one. Its a simple addition and I've added it to the steps.


    10 years ago on Introduction

    Great Instructables and easy to follow. I would suggest just one addition for security. It is best to use a 12v plug that have a fuse build inside, so if there is any shortcut for any reason, the fuse will blowup instead of making the wire to heat up and risk to get in fire depending of the value of the car fuse. And even if the car fuse blowup, it's often easier to change the fuse in the 12v plug than the one in the car, who often , are in a non comfortable place. The difference in the price worth it for the security and comfort it provide. P.S. Sorry for my limited English. I speak french.