Bad Courtesy Lights: Symptoms and Causes

Exiting your vehicle at night is much easier when you have a set of functioning courtesy lights. You’ll usually notice your courtesy lights, also called dome lights, located on your vehicle’s ceiling. Sometimes, courtesy lighting can also be found above your vehicle’s doors. They can come as a set or as a single light.

Courtesy lighting also includes the glove box light and lights mounted on either side of the sun visor mirror. There are also map lights that are brighter than courtesy lights for reading, and these are usually on either side of the courtesy dome light on higher end vehicles or newer ones.

These fixtures turn on whenever you open a door, illuminating the inside of your vehicle  or whenever you open the glove box or turn on the dedicated switch when the sun visor is down. Courtesy lights on newer vehicles are typically LED lights rather than incandescent bulbs.

When your courtesy light isn’t working properly, it can be a hassle. You might observe the following symptoms:

Symptoms of a Bad Courtesy Light

Make sure that the courtesy light controls haven’t been accidentally flicked into the on or off position. Apart from this human error, most of the symptoms associated with a malfunctioning courtesy light are connected to the light itself.

Lights Stay On

A malfunctioning courtesy light will sometimes remain on, even if the switch is turned to automatic or off. When this happens, the bulb will burn out more quickly. If your vehicle doesn’t have a battery saver function, it may kill the battery.

Lights Don’t Work

When your vehicle’s courtesy light doesn’t turn on, it can mean a problem with a fuse or a burnt-out bulb. It can also be due to wiring or module issues depending on the vehicle.

Dim or Blinking Lights

Your light may be fine one moment but suddenly weak or blinking the next. These are unusual behaviors for a courtesy light and should be investigated. Dim or blinking lights can often be traced to battery problems or intermittent wiring concerns.

Causes of a Malfunctioning Courtesy Light

The courtesy light in your vehicle can malfunction for a number of reasons, including the following:

Bad Bulb

A bad bulb is the most common cause for inoperative courtesy lights. Replacing the bulb can solve this problem.

Blown Fuse

A blown fuse can be the source for a number of electrical problems in your vehicle, including the courtesy lights not working.

Faulty Wiring

A short or an open in your vehicle’s wiring can also cause problems with the courtesy lights.  An experienced technician can help find and repair wiring issues. You can look yourself and see what you might be able to find, but don’t get in over your head.

Stuck Door Switches

The door switch is part of the system that alerts your courtesy lights when to stay open. Sometimes, the switch is visible as with a door jamb switch. But more often on newer vehicles, it’s built into the door latch inside the door and doubles as a “door ajar” switch. When it’s open, it’ll tell the light to stay open. If the door jamb switch isn’t closing properly, then the light might refuse to close when in the automatic setting.

More often on newer vehicles, the switch is built into the door latch inside the door and doubles as a “door ajar” switch.

–Richard McCuistian, ASE Certified Master Automobile Technician

Weak Battery

A weak battery can lead to dimming or blinking courtesy lights. But quite frankly, if your battery is weak, you have far more serious issues to deal with.

How Do Courtesy Lights Work?

Courtesy lights work on a circuit. When the door is closed, the circuit is open and the lights don’t turn on. Likewise, when the door opens, the circuit closes and the lights are activated. Most modern vehicles have switches that send signals to the BCM, which in turn activates the courtesy lights.

These lights have three common settings–on, off, and door. The door or automatic setting alerts you when a door is open and comes on when you get off.

Cost of New Courtesy or Dome Light Bulbs

If your courtesy light’s bulb is burnt out, then it’s time to buy a new one. You can get a new light bulb for around $10–$80. LED courtesy lighting sets are also available now, and some even have a universal fit.

A bad courtesy light isn’t usually cause for an immediate trip to the mechanic. It doesn’t play a vital role in keeping you safe on the road or ensuring that your vehicle is running. However, courtesy lighting does add a good deal of convenience to getting in and out of your ride, so you’ll want to fix a broken one as soon as you can.

Where to Get a New Courtesy Light Bulb for Your Ride

You’re going to need your courtesy light to locate important items in your interior when it’s dark.  But over time, the bulb inside your courtesy light can dim or fail, rendering it useless. Luckily, CarParts.com has a wide selection of courtesy light bulbs sold at unbeatable prices.

Shopping for a compatible courtesy light bulb for your vehicle is quick and easy when you do it online. Just go to our website, check for fitment using our vehicle selector, and filter the parts according to your preferred brand or price range.

There’s no need to worry about delayed delivery. Our distribution centers use the latest technology to guarantee that your orders are shipped out quickly and arrive in a matter of days.

If you have questions, don’t think twice about contacting us using our toll-free hotlines. We also have a 60-day return policy, so we can refund your money in case there’s a problem with your order.

Take a look at our selection now, and enjoy the best deals on courtesy light bulbs today!