How to Build a Fake Car Alarm Light

by Rose Kivi

A car alarm can discourage a thief from stealing a car--but so can a fake car alarm, if the thief thinks it is real. More often than not, the flashing light indicative of a car alarm moves a thief on to a car without an alarm. A fake car alarm is simply a flashing light that looks like a real car alarm light. It only costs about 5 dollars and a hour of your time to build a realistic fake car alarm that automatically flashes when the car is turned off and stops flashing when the car is turned on.

Step 1

Disconnect the car battery cables from the battery. Remove the negative cable first. To remove the battery cables, loosen the screw on the cable using a screwdriver. Once the screw is loosened, the cable will easily pull off the battery post.

Step 2

Strip 2 inches off the ends of the flying lead wires that are attached to your LED light using a wire stripper. Strip one wire at a time. To use the wire stripper, close the tool around the wire about 2 inches from the end of the wire. Holding the wire stripper tightly closed, pull the tool towards the end of the wire. The wire stripper will pull the plastic coating off the wire.

Step 3

Wrap the red flying lead wire around the positive battery terminal cable. The wire should be wrapped around the battery cable screw that you loosened when removing the battery cables.

Step 4

Run the red and black cables along the side of the engine compartment and push them through so that they run underneath the dashboard. Use electrical tape to tape the wires to the sides of the engine compartment so they don't move.

Step 5

Get access to the car ignition by removing the ignition housing. Access to car ignitions differs according to the car model. The best way to find access to the ignition of your car is to look in your car's manual. Once you have access to the car ignition, you are ready to move on to the next step.

Step 6

Locate the 12-volt positive ignition wire. To determine this wire, refer to the car repair manual.

Step 7

Strip 2 inches off of the end of the 12-volt ignition wire using a wire stripper tool.

Step 8

Twist the black flying lead lighter that is attached to the LED to the 12-volt positive ignition wire.

Step 9

Wrap electrical tape around the section of twisted black flying lead and ignition wires.

Step 10

Pop out the dashboard dummy panel where you want the LED light to display. Most cars have dummy panels in the dashboard. Dummy panels are sections that pop out of the dashboard without having to remove the actual dashboard. If your car does not have a dummy panel or if you cannot figure out how to pop out a dummy panel, refer to the car repair manual.

Step 11

Using a drill and bit, drill a hole in the removed dummy panel. Use a bit that will drill a hole that is the same size as the LED light.

Step 12

Put the LED light into the dummy panel. The LED should slide into the hole from the back of the dummy panel so that it is sticking out of the front of the dummy panel. Pop the dummy panel back into the dashboard.

Step 13

Put the battery cables back onto the battery, starting with the positive cable. Put the positive cable onto the battery post and tighten the cable screw until the cable is tight on the post. Then put the negative cable on using the same method.

Step 14

Test the fake car alarm. With the car ignition turned off, the LED light should flash. When the car ignition is turned on, the LED should turn off. If the fake car alarm is not working, go back and check all of your steps to make sure that all the wires are correctly connected.