What Does the Bulb Failure (Exterior Light Fault, License Plate Bulb, Brake Light Bulb) Warning Light Mean?

In order to help the driver maintain their vehicle, manufacturers have been using computers and sensors to monitor just about everything in a car. Modern cars are sophisticated enough now to detect when any exterior lights have stopped working. When a bulb goes out, the overall resistance in the circuit changes, which then affects the voltage for that circuit. The computer monitors the circuits for all of the exterior lights for any changes in voltage and then displays a warning light.

What the bulb failure light means

The computer will switch on the bulb failure warning light when it detects any non-normal voltage in any of the bulb circuits. If you see the light come on, check all of the bulbs to find the one that is not working. Be thorough when checking the lights as modern cars have quite a few that can turn on the warning light. Some harder bulbs to find include license plate bulbs, turn signals on the side mirrors, the yellow parking lights at the front of the vehicle, and the tail lights at the back that come on with the headlights.

When you find the bad bulb, replace it and the warning light should turn off. It is possible for false positives to occur in which case the entire circuit would need to be inspected for any damage.

Is it safe to drive with the bulb failure light on?

In most cases, the car is still driveable. Now this doesn’t mean you should ignore the light. The exterior lights are very important for warning surrounding drivers of your car’s position and actions. Having non-functional lights can also make you responsible for damages in the event of a collision.

If you need any help replacing bulbs or if the light won’t turn off, our certified technicians are always available to assist you.


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Jason

15 years of experience
344 reviews
Jason
15 years of experience
Nissan Armada V8-5.6L - Warning Light is on - Mineola, New York
Excelente. Jason es todo un profesional con mucho conocimiento en la mecanica, buena persona educado y amigable. Gracias Jason.
Ford Taurus - Warning Light is on - Jamaica, New York
Very Professional definitely takes his time to find out exactly what’s the problem with the car! I was up and running in no time ! Will definitely recommend Him to anyone having issues with cars!!!

Nicholas

11 years of experience
585 reviews
Nicholas
11 years of experience
Chrysler 300 V6-2.7L - Warning Light is on - Durham, North Carolina
Excellent diagnostician. Knowledgeable and caring. Created a desire for him specifically, to do the job. Hope we get him every time!
Honda Accord - Warning Light is on - Garner, North Carolina
I was very happy with Nicholas and his knowledge and expertise about diagnosing the issues with my car. He is honest, reliable and professional. He is now my Mechanic that I will call on for all my car's needs.I will also recommend him to my friends whom have been taken advantage of by other car shops as I have been, and are looking for someone honest , that will not take advantage of them Thank you so much Nicholas for resolving my issue with my car. I feel relieved and happy with the outcome

Tony

40 years of experience
12 reviews
Tony
40 years of experience
Cadillac Escalade EXT V8-6.2L - Warning Light is on - Stockton, California
Good,mechanic helpful ,smooth move but quick, friendly patience and deep experience as a mechanic,as a customer I recommend Tony Crockett if you need a mechanic.

Brent

8 years of experience
56 reviews
Brent
8 years of experience
Jeep Grand Cherokee V6-3.7L - Warning Light is on - Lithonia, Georgia
On time for appointment. Knowledgeable, he explained what he was doing & then explained his findings to me. Later he sent a text with the diagnostic findings,

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