How to Check Turn Signal Wiring

If you think you have a defective turn signal bulb, the best way to make sure your turn signal wiring is working is by using a test light. A test light will light up when the circuitry is functioning properly. There are several techniques for checking the turn signal wiring. Here are some simple steps for checking the wiring so you know that your turn signal is functioning correctly.

Difficulty: Moderately Easy

Instructions

Things You'll Need:

• Test light
• Spare turn signal bulb
• Gloves

Prepare the Test Light

1. Prepare the test light. Locate the turn signal socket and pull it forward for easy access.

2. Turn on one of the turn signals. Turn on either the left or right signal to run the current through the circuitry system.

3. Check the ground signal for integrity. Use the test light to determine if the ground signal is working; the test light will light up if it is working.

4. Test the positive side of the circuitry. Put the test light on the positive side of the socket to determine if it is working; the test light will light up if it working.

5. Use the spare bulb to determine if the turn signal will work. Insert the spare bulb onto the connector and wait for it to start flashing. The bulb will light up if the turn signal system is working properly.

Tips & Warnings

• The turn signal and hazard lights use the same switch
• Wear gloves when pulling out the turn signal switch to avoid scratches or scrapes from your car
• Do not allow the test light to come into contact with water or liquids