The function of the dome light is to illuminate whenever you open a door and switch off as soon as you close it, irrespective of whether you’re entering or exiting your vehicle. However, there are instances when the dome light may continue to stay on, even after the door has been closed. This brings us to the issue at hand – understanding why the dome light refuses to turn off.
Well, the dome light operates through several switches. One of these switches is stuck in the ‘On’ position, or something happens with your circuit and wiring. A malfunctioning dome light wears on your battery and can reduce nighttime visibility. So, let’s find out all the reasons why your dome light won’t turn off and how to fix it.
In the end, you’ll be able to use one of these solutions to fix a dome light that stays on.
How does your dome light work?
The dome light has several switches, as I’ve mentioned. The central control of the dome light is usually an adjustable knob on the dashboard, on the left side of the steering wheel. Still, the standard controller can also be on the dome light switch on the headliner.
Other switches that control the dome light are on each door and sometimes even the trunk on some vehicles.
The dome light has a positive wire connected directly to the light and one negative wire connected to the dome light through the switch. The door switch, also known as the pin switch, has one terminal connected to the ground side of the dome light circuit.
The threaded metal part of the main switch is connected to the vehicle’s ground through the metal part of the door switch. These switches work backwards from what most people would expect, such that when the door is open, the circuit is completed because the contact on the switch is closed to the ground.
In addition, the light has a fuse that covers multiple switches in parallel; that’s why the dome light will come to no matter which door you open. Finally, some vehicles have a timed control in the ignition switch. So, if the dome light won’t turn off, it means that one of the switches is stuck in the ON position.
Can i fix it by myself?
You can quickly fix a dome light that won’t turn off at home in most cases. Nevertheless, you may need a mechanic if the cause of the problem is the electrical circuit. Alternatively, you may want an extra pair of hands if the problem is with the door.
Common causes and how to fix a dome light that stays on
1. Damaged or missing control switches
The first thing that you’ll want to do is inspect the main switch on the dome light or dashboard.
Dome light switch
Let’s start with the dome light switch on the roof of your car. Someone may have accidentally bumped it and changed the position, or it could be damaged.
Most vehicles have a three-position slide switch. There’s the OFF all the time position on one end, then there’s ON all the time on the other end, and the DOOR position in the middle. The “Door” position means the dome light will be on when the door is open and then delays for 15 – 30 seconds and turns off after the door is closed.
Check to see that the position on the switch is not in the ON position. Hence, slide it to the middle if this is the case. Then see if it turns on and off with the door. Make sure to wait a few seconds, and if nothing happens, you can slide to the OFF position. Again, if the dome light does not turn off, it’s likely that the main switch is broken, and you’ll have to let a professional look at it.
Dashboard switch
Now, if you have a dashboard switch, also known as a dimmer switch, you may have turned it all the way up. In this case, even the other dashboard lights will be on, making the dome light turn on. This dimmer light is ideal for having the dome light on when doing something in the car when you don’t want to open a door.
To this end, if you have the dimmer switch turned up all the way, turn it down, and the dome light will turn off by itself. If the dome light does not turn off with the dashboard switch at the lowest setting, you have a damaged dashboard switch. Hence, a professional is better equipped to fix this issue.
2. Faulty car door switch
The next thing that could be causing the dome light to stay on is a faulty door switch. For this problem, you’ll have to inspect one door at a time until you find the malfunctioning switch.
There are two types of door switches; door jamb and door latch switch. Let’s find out how to diagnose and repair these two types of switches.
Door jamb switch
Step 1: Inspect Each Door
With the dome light switch in the “Door” position, open and close each door, ensuring that you see which door does not turn off the dome light.
Step 2: Locate the Door Jamb Switch
At this point, you’ll have found out which door has a damaged switch. It’s time to locate that switch, which is usually along the door jamb or the door frame. This switch is likely stuck in the ON position.
Manually press the switch and see if the light deactivates. You should feel a click when you press on that switch. If it has lots of play or no clicking sound, you have a faulty switch.
Step 3: Replace the Switch
You will need:
- Screwdriver
- New door jamb switch
How To:
- Peel back the rubber on the switch to locate the grounding screw.
- Loosen the screw such that you can see the electrical connector to the switch
- Slide the electrical connector off and connect a new replacement switch
- Screw the new button in, and the dome light will turn off when you close the door
Door latch switch
Some doors have a latching switch instead of a door jamb switch. If your door latch is damaged or the door does not close fully, it prevents the latch from interrupting the circuit. Hence the dome light stays on. A good slam will fully close the door, and the dome light will turn off in most cases. However, you don’t want to slam the door every time to switch off the dome light.
The first thing you’ll need is to inspect the latch switch to see that it’s working correctly. All you do is press the latch to the door closed position using a screwdriver. The dome light will turn off because the latch has interrupted the circuit.
Here, the problem is with a door that does not close entirely, meaning it is sagging off-kilter, and the latch is not fitting in properly. Moreover, if the door is misaligned, you’ll see visible damage on the striker. It means that the door has been hitting the striker, thus damaging the door latch over time.
Here are the steps for fixing a faulty door latch switch.
Step 1: Check the Door Hinges
Checking the door hinges is pretty straightforward. However, when fixing a sagging door, you may need someone else to help lift the door or use a floor jack.
Step 2: Loosen the Bolts
Vehicle doors have two hinges that are held on with two bolts. Loosen the bolts just a little bit, don’t remove them. You’ll need a 12 mm door hinge bolt wrench.
Step 3: Lift the Door
Use the floor jack to lift the door until you feel some tightness to the door.
Step 4: Tighten the Bolts
Get back to the bolts and make sure they are tight. You’ll also have to make sure that the latch aligns appropriately. Once you complete tightening the bolts, the door should close smoothly, and the dome light will turn off once you close the door.
3. Not fully closed door
The dome light relies on the door sensors to know when to shut off. If one of the doors does not close completely, it will cause the dome light to stay on. Hence, you should ensure that no doors pop up as open on the dashboard. After this, confirm that all doors are closed, and the dome light will shut off if one of the doors is not fully closed.
4. Not properly latched front hood
Some vehicles have a latching switch in the front hood. This switch turns off the interior lights, so the dome light will stay on if the hood is not fully closed. In most cases, a hood not latched in properly will cause the alarm to go off after closing all the doors.
After ensuring that all the doors are closed, check that the hood is latched in properly. This will cause the dome light to turn off a few minutes after closing all doors.
The cost of fixing a dome light that stays on
In some cases, you may need a mechanic to inspect the wiring if you can’t find the defective switch. Remember that the interior lights are crucial in a vehicle’s operation, so fixing them is vital.
Professional mechanics typically charge $50 to $100 to fix a dome light that stays on. However, this figure depends on the location and car model.
Conclusion
I hope I’ve answered your question about “why my dome light won’t turn off?”. As you can see, the dome switch is likely in the wrong position, or you have a faulty door switch. In other cases, a misaligned door can cause the dome light to stay on, or the front hood is not latched in properly. Nonetheless, you can now find the correct fix depending on the issue you see.
Good Luck!
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Frequently asked questions (FAQs)
1. Will a dome light drain a car battery?
Yes. A dome light that stays on will eventually drain the battery if the engine is off. Nevertheless, this will depend on the battery’s size and the type of dome bulb you’re using. If you have a big battery with a great reserve capacity, it will take a long time for the battery to be drained completely. However, the battery may refuse to crank your car if the voltage is too low.
If you are running an incandescent dome light that’s power-hungry, it will draw up to 50 amps; hence it can drain the battery faster than an LED dome light that draws only five amps.
It’s best to remove the dome bulb that stays on until you have the problem fixed instead of leaving it on.
2. How long can dome light stay on?
The dome light can stay on for up to four days if you have a fully charged battery. That’s assuming it’s drawing only five amps from an 80Ah battery. For a different type of battery, it can drain the battery overnight even when the battery is fully charged in the summer. Of course, the battery will drain faster in cold weather.
3. Can leaving a single interior light on in your car overnight drain your battery?
Again, this depends on the bulb type and battery’s reserve capacity. So, if you have a bulb that draws as much as 50 amps from an 80Ah battery, it’s capable of draining the battery overnight.
4. Are interior LED lights bad for your car?
No, LED lights are perhaps the best type of bulbs to have as your interior lights. LED lights consume less energy than halogen and incandescent lights. Experts estimate that LEDs are up to 80% more efficient than conventional lights.
In addition, LEDs have a long lifespan, generate less heat, and come in a wide variety of colors.
5. Can you drive with the dome light on?
Driving with the dome light on is not illegal. Nevertheless, it can result in distracted driving if you use it to look for something when moving. Moreover, increased brightness in the cabin can be hazardous in that it can limit your field of vision or reflect off the windshield, reducing road visibility.
Furthermore, your car is supposed to dim the lights in the cabin when the headlights come on. This is meant to improve night vision and avoid dazzling your eyes at night. Hence, driving with the dome lights on is counterproductive when the headlights are on.
Read more: Headlight won’t turn off: The causes and solutions
