Make Your Own LED Light Bulb Tester From 9V Battery!




Introduction: Make Your Own LED Light Bulb Tester From 9V Battery!

About: Everything about automotive LED lights

When I buy LED lights online, I always want to make sure that they work before I go through the long and tiring process of installing the lights. Installing LED lights only to find out they don’t work would be such a annoying thing so to prevent that, I decided to make a tester out of a 9V battery I had laying around.

You don’t even need any special tools or parts, all you need are:
1. A 9V Battery
2. Black Electrical Tape
3. 2 pieces of 18-22g wire (color coded)
4. Wire Strippers

This simple DIY only takes a few minutes of your time and will be able to save you hours of headache in the future!

Step One:
Gather your materials together. Make sure to only use this 9V battery, never use any battery exceeds 12V which can potentially damage the LED. Using a battery less than 9V may not allow the lights to even turn on.

Step Two:
Strip some plastic sheathing off of both ends of the wires and hook the wires to the battery's positive and negative. (Make sure to hook the red wire and black wires to the battery positive and negative terminals, respectively).

Step Three:
Use the black electrical tape to cover the positive and negative terminals up.

Step Four:
Now you have made your own LED tester. You can connect the red and black wires to the LED bulb to check which side of the LED bulb is positive and also to see whether a LED bulb is defective (NOTE: If an LED bulb does not light up at the first time, please flip the two wires around and try again)

1 Person Made This Project!


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5 years ago

Uh, I burned out a led sequin thanks to you. Bad advice.


6 years ago

What a great idea.

Would testing the LEDs this way show them as bright as they would be once installed on the car? I ask because a 9V battery is just a weak, household battery, compared to a car's electrical system.

I'd like to test the LEDs for exactly how bright they'll look on my car, not just whether they work or not. Because if they are too dim for my purposes, I'd rather not begin installing them. Does my question make sense?


7 years ago

Hey, just wanted to say that 3V is able to make LED's shine pretty bright. If I were u, I'd add some 350 ohm resistors to the + end of the LED's. It keeps them shining longer.