Why Lights Won’t Turn Off In Car – Causes & Fixes

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Why lights won’t turn off in a car? A few years back, this question would seem like taking a USMLE.

I first noticed that the interior light on my car wouldn’t turn off during my last visit to Minnesota City. I’d traveled from Winona for the annual Summer Beer Dabbler festival.

But behold, more than half of the entire 89-mile travel had the interior lights of my car on. Of course, the car battery and alternator suffered the brunt.

Three things can happen to the lights in your car. First, they can go dim. This usually occurs if there’s a failure of the alternator.

Corrosion on your car battery can cause the lights to flicker. The third issue is when the lights stay on indefinitely. The third issue is what I’ll be discussing with you here.

We know everyone loves light but having your car lights on 24/7 is not only not right but also car damaging.

There are four important lights in your car that should go on and off at given times while driving.

The headlights, interior lights, dash lights, and parking lights are located in different sections of your car. They also perform different functions.

Why Lights Won’t Turn off

There are several reasons the light of your car won’t turn off. Depending on the light in question, a stuck or broken switch can cause your car lights to stay on.

Improper closing of the car door is another factor to consider. A faulty engine timer, failed automatic lights, broken headlight relay, crossed circuits, and a disrupted auto feature are all culprits.

For a proper diagnosis and solution, it’s not right to narrow the factors to one.

Typically, the interior lights of your car can operate either manually or automatically. Ideally, a gentle press on the different manual switches should turn on or off your car’s roof lights. The same manual procedure should apply to the dashboard light and the light on your car door.

At other times, a simple opening or closing of your car doors could turn these lights on or off automatically.

However, if there’s no opposite reaction whenever you press the switches or open and close the car door, there is a possible malfunction.

In this case, the lights will stay on indefinitely. When this happens, then there’s a need for you to take an action.

Now, let me walk you through the various car lights and what can cause them not to go off whenever you press the switch.

Why Interior lights Won’t Turn Off: Causes And Fixes

What Are Interior Lights?

The interior lights of your car are the lights installed in the consoles, the trunk, the doors, and the ceiling or roof of your vehicle.

They can also be located between or above the visors and any other strategic areas in the car. The primary function of these lights is to illuminate the inside of the car for passengers.

You can use the lights to search for in-car lost objects, fasten your seat belts, read books, study location maps, or safely store things in the safe. They are otherwise called courtesy lights or dome lights.

The interior lights should go off when you press the switches on the ceiling of your car. When you close the doors, the lights should turn off and come on when you open them.

But the lights can refuse to go off even after pressing the switch to ‘off’ or closing doors.

Causes And fixes Of Interior Lights That Won’t Turn Off

Two things are likely responsible.

Broken Door Switch

The interior lights often work with either the door switches or an automatic feature.

A broken door switch can be the reason your dome lights stay on. You can check the door switch.

Simply open the car doors and locate the door switch. When you open the car door, you can easily locate the switch if it is in an open place.

Press each switch and if the check which light stays on, then note there’s a problem. A clicking sound from the light when you push the switch means that the door switch is in good condition. If not, you have a broken door switch in your hand.

If the door switch is broken, the interior lights will never shut off because the car always feels the doors are open.

Broken Dome Light Knob

Another reason your car’s interior lights won’t go off is when the control knob is faulty.

You may notice that the dome light stays in the on position after shutting down your engine. The control switched may have activated and stuck in the on position and unable to return.

The first thing to do is to adjust the light to reduce the brightness until you get to where you can resolve the stuck knob.

Dash Lights Won’t Turn Off: Why And How To Fix

What Is A Dash Light?

The dash lights are the lights that are integrated into your car dashboard that turn on and off.

Like all auto interior lights, the dash lights are intended to illuminate the accessories, gauges, and other internal parts of the automobile. Dash or flashlight is blue and yellow.

Under normal conditions, the dashboard lights should go off as soon as you close the car doors. But when they don’t there are a few things to suspect as responsible.

Causes And Fixes Of Stay-On Dash Light

Let’s take a look.

A Faulty Ignition Switch

The ignition system controls when the dash lights come on or go off.

Once damaged or worn out, the ignition system will cause some internal components to break. As a result, the electrical system will receive a short circuit.   

Faulty Battery

In today’s auto design, the amount of battery voltage that gets to the control module can affect the functionality of the lights.

The dash lights and other interior lights will start to receive messages from the Morse code once the battery is faulty. The consequence is that the dash lights won’t turn off.

Anti-Lock System (ABS)

Any issue with the antilock system causes damage to the braking system.

Failed braking will cause the functioning of the antilock braking system (ABS) and its features to switch off. Once this happens, the dash lights are affected because they’re directly connected to the ABS.

Low Engine Oil

A low engine oil warning light will come and stay on the dashboard indefinitely. If the engine oil level is extremely low, the warning light will still stay on, even after switching off your car.  

Dirty Battery Cables

The cables of your car battery can also become loose or dirty. When it happens, the dash lights can start to flicker and then stay on even after turning off the car engine.

Headlights Won’t Turn Off: Why And How To Fix

What Is a Car Headlight?

Your car headlight or headlamp is the light installed on the front part of your vehicle. They help illuminate the road ahead.

They are designed to offer you full visibility on the road. They help to reinforce your visibility when driving in unfavorable weather conditions.

They are usually white and are the only legal color of a headlight.

Essentially, they light the road ahead of you when it’s dark or cloudy. When it refuses to turn off after switching off your engine, there is a problem.

Causes And Fixes Of Stuck Headlights

Here are potential suspects:

Automatic Light Failure

Most modern cars come with automatic headlights that turn on and off automatically. Once the automatic switch system fails, the headlights might stay on for as long as it is left unrepaired.

The first remedy is to use the parking brake. The brake is designed to automatically disable any automatic function in your car. It can help switch them off but in most cases, it won’t.

Alternatively, you can replace the entire automatic light system. If the issue persists, you can take off the whole auto system.

Bad Relay Signal

Another possible cause of headlights not turning off is a broken headlight relay. When the relay breaks, it’ll start sending bad or wrong relay signals to the headlight system.

As a result, the headlights will stick on. In most cars, the relay system is installed under your car hood. It controls the length of time the headlights have to wait before shut off.

If you give the relay system a gentle tap and it flickers or turns off, then you can be sure that it is the problem. The best solution is to swap or replace the headlight relay.

Faulty Engine Timer

Some vehicles are designed with timing technology. The engine timer technology allows your headlights to stay on for a certain number of minutes after turning off your engine.

The headlights will thereafter turn off. However, once the system has stopped working, the headlight can stay on indefinitely.

The on-the-spot thing to do is to turn off the light before shutting off the engine. If this works, then the problem is the faulty engine timer. You can replace it later.

Failing One Headlight

There’s a chance that one of the headlights will stay on. When this happens, two things are likely responsible.

First, one of the headlights might be having issues, perhaps it is burning out. It could also be that the faulty headlight bulb is getting in sync. In that case, it will stay on even after you shut off your engine.

What you should do is to replace the burnt bulb with a new one. If the automatic running light is the problem, you can get the problem fixed with a technician.

Parking Lights Stay On When Car Is Off: Why And How To Fix

As the name suggests, car parking lights are the lights that come up each time you press your foot on the brake pedal and park.

Installed at the front and rear of your car, parking lights come in white or amber, and red. The red color is located at the back while the white or amber is the color of the front parking light.

Its responsibility is to illumine the surrounding of your car while increasing the visibility of the car in dark, busy, or cloudy situations.

Although it is not used in most parts of the world, car parking lights still feature in many auto manufacturers’ products. What will cause the parking lights to fail and what are the remedies?

Faulty Blinkers Relay

When you’re driving, the turn signal lights can come up and stay in the on position indefinitely. The turn signal relay can be the cause. It is either that the turn signal relay is bad or its arm has one of its springs broken.

Broken Signal Turn Spring

The spring is responsible for shutting down the blinking light after you’ve completed a turn. If the activated spring breaks, the turn signal will stay in the on position and won’t turn off.

One of the symptoms is a strange feeling you get on your steering arm. The spring is responsible for returning the arm to its original place after complete turning. But this will not happen because the spring itself is broken.

Clogged Auto-Off Features

Like it can happen to the interior lights, dash lights, and headlights, the parking lights can also suffer from disrupted auto-off features.

It may be that some foreign objects are clogging the way of the auto-off sensor. The relay sends a signal to the sensor which in turn turns off the parking lights.

However, a break in communication between the sensor and relay due to a glitch causes the lights to stay on. You may need a technician to help locate the position of the relay system in your vehicle.

Final Thoughts

The importance of your car lights cannot be overemphasized. Their health can also mean your safety and if they are in a stable and good state, you’ll have a rest of mind when driving any time of the day.

You may tend to think these issues are easy to handle and so choose to go a DIY way. However, restoring your car lights to a normal state requires a bit of expertise.

If you ask me, I will recommend that you hire a technician. They have the requisite skill to diagnose the problem and professionally nip them in bud.

This is true especially if you’re looking at upgrading from the standard halogen bulb to LED car lights. Most times, it’ll require proper tools and knowledge to tackle the lighting system of your vehicle.