How to Wire Auto Emergency Lights

Automobile emergency lights, or emergency flashers, are an important safety feature. Emergency flashers let other drivers know there may be a problem or hazard with the vehicle using emergency lights. Emergency flashers are wired through both the head and tail lights on a vehicle so that drivers behind and in front can know the vehicle is in trouble. Replacing or wiring a burned out emergency flasher is a matter of pinpointing which flasher is out, then rewiring it.

Things You'll Need

• Socket set
• Replacement bulb

Instructions

1. Turn the vehicle's ignition then press the hazard light button. Visually inspect to see what emergency flasher is out. There are four on cars and trucks: the front left, front right and rear left and right lights.

2. Open the hood of the vehicle and use a socket set to remove the negative battery cable.

3. Remove the screws holding the headlight assembly in place on the inside section of the headlight frame assembly. Use a screwdriver to pull it loose so that you can access the bulb holes on the back of the assembly. For rear tail light wiring, pop the trunk and access the screws holding the tail light assembly in place. Remove those screws with a screwdriver.

4. Unplug the plastic wiring harness that the light assembly connects to at the rear.

5. Twist the bulb socket to the left, then remove it through the rear of the bulb housing assembly. Pull the old bulb out of the socket and push the new one in. Slip the bulb socket back through the hole in the headlight or taillight assembly. Twist it to the right to secure it.

6. Plug in the emergency light's plastic wiring harness.

7. Mount the headlight or tail light assembly, replacing the retaining screws with the screwdriver. Also replace the negative battery cable.

References

• "How to Diagnose and Repair Automotive Electrical Systems (Motorbooks Workshop)"; Tracy Martin; 2005