The main reasons behind dashboard air vents not working are damaged fuse or relay, malfunctioning blower motor, faulty blower resistor, jammed cabin air filter, low level or refrigerant, clogged air intake, broken hoses, faulty compressor, damaged condenser, and stuck blend door actuators.
Keep reading this article to find out more about these issues that keep your air vents from working properly and learn how you can fix each of these issues. You’ll also learn how to unclog the air vents in your car and prevent the growth of mold. Let’s dive in!
Table of Contents
- Why Dashboard Air Vents Not Working [Reasons + Solutions]
- 1. Damaged Fuse Or Relay
- 2. Malfunctioning Blower Motor
- 3. Faulty Blower Resistor
- 4. Jammed Cabin Air Filter
- 5. Low Level Of Refrigerant
- 6. Clogged Air Intake
- 7. Broken Hoses
- 8. Faulty Compressor
- 9. Damaged Condenser
- 10. Stuck Blend Door Actuator
- How To Unclog Air Vents In Car?
- Method 1: White Vinegar and Warm Water
- Method 2: Sanitizing Enzymatic Cleaner Spray
- Method 3: Car Steamer
- How To Prevent Mold Growth In Your Car?
- Clean Air Intake
- Dry The AC Vents
- AC Off And Blower Motor On
- How To Remove Dashboard Air Vent?
- How often should air vents be cleaned?
- How do I increase the airflow in my vents?
- What controls the vents in modern cars?
- Why are side vents used in cars?
Why Dashboard Air Vents Not Working [Reasons + Solutions]
Most modern vehicles are reliant on the HVAC (Heating, Ventilation, and Air Conditioning) system to maintain the correct temperature inside them. When it works properly, you can keep your car warm in cold weather and vice versa.
It’s annoying to find the dash vents not blowing air properly in your vehicle as it can turn a comfortable ride into a terrible experience. Let’s take a look at the most common reasons behind this agonizing issue:
Note: You can also read how to fix Clicking noise in dashboard when the Car is off.
1. Damaged Fuse Or Relay
The first thing you should check when you find some vents not blowing air in the car is to check the ventilation fuse. The blower motor won’t be able to function properly if you have a faulty ventilation fuse.
The next thing you need to check is the relay that supplies power to the blower motor. You can check whether it works by swapping it with a relay with the same part number.
If your ventilation fuse is blown-out, you need to replace it. It can be both a temporary or permanent fix depending on your car. If replacing it once fixes the issue for you, it’s a permanent solution. The ventilation fuse is located at the fuse box found in the engine bay for most vehicles.
But if the fuse keeps blowing out, there are other underlying reasons behind it. You’ll have to find out these issues and fix them. If the relay is faulty, you need to replace it to get the blower motor running properly again.
2. Malfunctioning Blower Motor
There’s a motor located behind the dashboard in your car that blows the air through the vents. This motor is called the blower motor and it’s a critical part of the HVAC system in your car. You’ll hear the blower motor running and changing pitch when you switch the temperature during normal operation.
But if it goes bad, you won’t hear any sound coming from it as it won’t move. A motor normally becomes faulty when it undergoes wear and tear with time or due to electrical issues. If it becomes damaged due to any reason, you won’t get any hot or cold air from the vents.
To inspect whether a blown motor is damaged or not, you first need to rule out that the fuses and relays of the HVAC system are fine. Because if there are issues with the blower motor relay, it won’t get power and you might mistakenly diagnose that you have a faulty blower motor.
Once you’ve made sure that the fuses are relays are functional, connect an amp meter to the power wire of the blower motor. Turn it up to full speed and the amp meter should read anywhere between 8 to 15 amps.
If the reading doesn’t fall under that bracket, that means that your blower motor has gone bad. Have your blower motor replaced by an experienced mechanic as it’s a tricky component and it requires expertise to do this job.
3. Faulty Blower Resistor
There’s a resistor that helps the blower motor to do its job properly. It’s called the blower resistor and it controls the flow of air that gets blown to the car according to your instruction through the vent controls. In other words, it controls the fan speed of the blower.
If the blower resistor goes bad, the flow of air will no longer be properly regulated and it could be the reason why your dashboard vents are not working and blowing hot or cold air when needed. If your blower motor is stuck at one constant speed, that’s a good indicator that you have a faulty blower resistor.
The blower motor resistor has to be replaced when it goes bad. Replacing it is an easy job and you can do it yourself. You’ll need a small ratchet and a socket set to complete this job. Follow these steps to replace the blower resistor:
- Let the blower resistor cool down for a few minutes after use.
- Disconnect the negative terminal of the battery.
- Empty the glove box first as you’ll need to remove it to access the resistor.
- Take off the support of the glove box strap from the hook on the outside.
- Remove the glove box.
- Take off the screws that put the blower resistor in place.
- Disengage the wire harness locking tab.
- Disconnect the wire harness from the blower motor resistor.
- Remove the resistor from the housing.
- Put your new resistor in place of the old one.
After replacing the resistor, reverse-engineer the process and put everything back together. If you hire a mechanic to do it, it’ll cost you an additional $70-$80 in labor charges. Since it is an easy job, it’s better to do it yourself.
4. Jammed Cabin Air Filter
The cabin filter cleans the air before it passes through the vents of your car. These filters can become clogged with time when they’re not maintained properly. When they get clogged, you’ll get a low flow of air.
A jammed cabin filter is one of the most common reasons behind the dashboard vents not working. If you fire up your AC at full blast and notice that the flow of air is low, chances are you have a clogged cabin filter.
If the cabin air filter is clogged, it needs to be replaced with a new one. The cabin air filters are located under the passenger’s seat in most vehicles. It can also be under the bonnet. Refer to your owner’s manual or do a quick google search to find out where it’s located in your car.
If you have managed the successfully locate the filter, unscrew the mounting screws that hold it in place. The filter will look dirty from the outside even when you’ll get a look at only the side view first.
Remove the filter with your hand. Some vehicles also have two cabin air filters. In that case, remove both of them and replace them with new ones. They only cost a few bucks and you can solve your problem easily if this was the issue.
5. Low Level Of Refrigerant
Another reason behind your air vent not working is a low level of refrigerant. It’s a common issue that causes air barely coming out of vents in car. When there’s a low level of refrigerant in your car, you’ll notice that the air blown through the vents isn’t as cool as it’s supposed to be.
In some cases, it can get a lot worse and you’ll see the AC blowing hot air in your car instead of cold air. When the refrigerant is emptied out, the AC in your car will no longer be able to blow air.
How do I fix my car AC not blowing air? If you think that you have a low level of refrigerant in your car by looking at the symptoms above, it’s time for a refill. Add refrigerant to your AC and it’ll run as it was before all the problems began.
The process of refilling the refrigerant in your car is called recharging your AC system. There are DIY recharging kits available if you want to do it yourself or you can have it done by a mechanic.
6. Clogged Air Intake
The air in your car flows through two main areas. One of them is the area by the vents that are located next to the lower half of the windshield. The second one is through the cabin of your car. While the first one collects air from outside the vehicle, the second one is for re-circulated air.
These two areas must have a proper flow of air for your HVAC system to work properly. But with time, dirt and debris can pile up the areas and make it impossible for the vents to pass air through them.
You need to clean the areas so that air can pass through them. You need to locate them first in order to do that. These air intakes are normally found at the footwell of the passenger side and the base of the windshield.
Inspect these areas and if you see that there is a build-up of dirt, clean it with a duster, toothpick, or other tools of your preference. Take your time while doing this to make sure you clean it well. You’ll notice a better flow of air immediately once you unclog the air intake.
7. Broken Hoses
There are many hoses in your car that transport fluid but are also connected to the ventilation system in your car. If any of these hoses are broken or damaged in any way, they’ll leak air and the ventilation system won’t function well.
Torn hoses can even lead to air coming out of wrong vents in car. It can also cause a refrigerant leak and you already know how bad it is for your ventilation system when you run low on refrigerant.
If you suspect whether the issue is being caused by a broken hose, you’ll need to locate it first. Once you identify the leak, the next thing to do is seal it. There are many patching kits available that you can use to seal a leak in hoses.
8. Faulty Compressor
The compressor is the heart of AC that compresses the refrigerant and lets you enjoy the cool air coming from it. It essentially increases the pressure of the refrigerant when it’s in a gaseous state. When the compressor goes bad, the refrigerant won’t be pressurized and you won’t get cool air.
Testing if your compressor has gone bad is easy. Take a wrench and socket and connect them to the end of the compressor. If the compressor doesn’t spin, that means it has gone bad.
The bad compressor needs to be replaced to get your AC running normally again. Follow these steps to replace the compressor in your car:
- Empty the refrigerant in your car.
- Pull off the fan belt.
- Take off the steering pump if it gets in your way.
- Unscrew the bolts to access the compressor.
- Pull the lines that are connected to it.
- Remove the compressor.
- Put the new compressor in its place.
Now you’ve successfully replaced the compressor in your car. Compressors are on the expensive side as they can easily cost between $200- $300 depending on your car. Make sure you get the right compressor for your car by following your owner’s manual.
9. Damaged Condenser
If the compressor is fine, another culprit that could be causing this issue is the condenser. It cools down the temperature of the gas before sending it out to the dryer in your AC. When the condenser becomes gets clogged or goes bad, your car will overheat as the flow of cool air from the AC will be poor.
You can do a visual check on the condenser and see if it’s clogged up. It’s also common for condensers to leak refrigerant when it goes bad. It affects the other parts in your AC system when it leaks and can make them go bad as well.
Replace the damaged condenser in your car by following these steps:
- Flush the refrigerant in your system.
- Pull off the front grill of your car.
- Remove the cross member at the top by unbolting it.
- Unbolt the lines connected to the condenser.
- Put a piece of cloth in the line to prevent air from getting into the AC system.
- Slide the condenser out.
- Add an ounce of peg oil to the condenser before you put it in the car.
- Install the new condenser in place of the old one.
- Put everything back together.
That’s all you need to do to replace the condenser in your car. When you notice that your condenser is clogged or leaking, you need to act quickly and replace it immediately so that it doesn’t lead to other problems.
10. Stuck Blend Door Actuator
The reason that you can change the direction of airflow is the blend door actuator. If you want to blow air to your face instead of your feet, you do it with the help of a blend door actuator.
The blend door actuators flip between being open and closed depending on the settings you choose on the climate control. With time, these blend door actuators can get stuck.
When they get stuck, you won’t get the proper flow of air. You’ll often hear a clicking noise when these actuators go bad. You can take your car to a dealer and have him scan the car. He’ll confirm if you have a bad actuator.
It’s a good idea to replace the blend door actuator when it gets stuck. Sometimes, it’s possible to repair the actuators if one or more of the teeth of the gear is broken. But it’s better to replace them to make sure that your HVAC system runs well and you don’t have to visit the mechanic every now and then.
How To Unclog Air Vents In Car?
When you don’t clean the air vents in your car or it gets clogged, water vapor forms and creates a moist environment that’s ideal for mold growth. It can lead to coughing, sneezing, or breathing problems for you.
It’s a good idea to clean the air vents once a month to make sure your car doesn’t get polluted and builds a musty odor. There are many methods you can use to unclog the air vents in your car depending on the level of debris.
Method 1: White Vinegar and Warm Water
Add white vinegar and warm water in equal proportion to make your own air vent cleaner. Some people can’t tolerate the smell of white vinegar. If you’re one of them, use lemon-scented vinegar.
You can also add a teaspoon of lemon juice to the mixture of white vinegar and warm water if lemon-scented vinegar isn’t available to you. You’ll need a foam paintbrush. Follow these steps to clean the air vents in your car:
- Dab the foam paintbrush in the vinegar solution.
- Gently shove the brush between the vents and clean it.
- Rinse the dirt collected on the brush and repeat the process.
- Use a towel to wipe off the excess moisture created by the solution.
Method 2: Sanitizing Enzymatic Cleaner Spray
The enzymatic cleaner spray is a great disinfect spray that does a great job at cleaning the debris from both the AC and the air vents. It’s commonly available and also comes with a straw so that you can easily apply it. Here’s how you clean the air vents using enzymatic cleaner spray:
- Close all the doors and windows in your vehicle.
- Turn off the ignition in your car.
- Turn the AC off.
- Attach the straw to the spray.
- Put the straw in the vent carefully and spray the disinfectant.
- Do the same for all the air vents in your car.
- Turn on the engine.
- Let the AC run at maximum settings.
- Spray the intake duct below the glove compartment.
- Get out of the car and spray the air intake in your car.
- Turn off the engine again.
- Open the doors and windows to ventilate your car.
Method 3: Car Steamer
When the dirt has accumulated for a while and it has gotten stuck, the first two methods won’t do the trick. You’d need the help of a professional car steamer to get the debris out of your air vents.
Car steamer is a great tool that will not only disinfect the vents but also get rid of the tough dirt and mold that is stuck strongly in there. Follow these steps to clean the air vents using a professional car steamer:
- Pass the nozzle of the steamer slowly to every air vent.
- It’ll clean up the dirt stuck inside and on the vents.
- Wipe the AC vents with a towel to remove the moisture.
How To Prevent Mold Growth In Your Car?
Mold growth can lead to a wide range of health problems for you and your family. Following these simple tips will help prevent mold growth in your car over the long haul:
Clean Air Intake
The main areas of mold growth are the air intakes when they become dirty. As soon as you see a build-up of dirt in the air intake, clean it. Taking care of the air intake once a week and cleaning it will prevent the growth of mold in it.
Dry The AC Vents
Every three or four months, turn off the AC and let the blower motor run at full capacity. Leave the car doors and windows open when you do it. Doing this will dry out the AC vents. Mold only grows when there’s moisture and drying the vents will minimize their growth.
AC Off And Blower Motor On
The process here is just like the previous one but a little harder to execute as it requires consistency. Whenever you turn up to your destination, turn off the AC a few minutes before that and let the blower motor run to dry the vents.
You may not always remember it or have the time to do it every time you drive your car. So, do it when you can to keep mold growth in your vehicle to a minimum.
How To Remove Dashboard Air Vent?
If you take your car to a mechanic, dashboard air vent replacement can easily cost a few hundred dollars. But if you decide to do it on your own, you can save a lot of money by skipping the labor charges.
Removing the dashboard air vent and replacing it with a new one isn’t too complicated. Follow these steps to remove the dashboard air vents from your car on the driver’s side:
- Take off the headlight switch in front of the air vent.
- Disconnect the cables attached to the switch and pull it out.
- Remove the grille by unscrewing the screw that holds it in place.
- Take out the wires from the red 1LED.
- You can pull out the dashboard vent and replace it.
The same process applies to the middle vents as well. First, you’ll have to remove the buttons and use flat blades to remove the center vents. After that, you’ll be able to move the frame out and replace the vents.
How often should air vents be cleaned?
At the very least, you should clean the air vents at least once a year. But if you have more time to spend on your car, clean the air vents once or twice every month using the vinegar solution.
How do I increase the airflow in my vents?
Dirt usually piles up on the cabin air filters and air intakes which end up reducing the airflow. Replacing the cabin air filter and cleaning the air intakes will increase the airflow in your vents.
What controls the vents in modern cars?
Modern vehicles have multiple actuator motors that can be adjusted by using the climate control module. These actuators open to a certain level to give you the desired flow of air in the right direction.
Why are side vents used in cars?
The purpose of side vents is to let the hot air from the engine bay escape into the environment. Sometimes, it doesn’t do anything and it’s only there to enhance the design of the car.
It’s a horrific experience to find your dashboard air vents not working when you’re enjoying driving your vehicle peacefully. But now you know how you can address this problem if you face it again.
We hope this guide will help you pinpoint the exact issue that’s causing the air vents to not work properly in your car. Leave a comment below if you have any more questions about dashboard air vents.
About John M
John contributed as a technical head at an automobile company just for 2 years after his post-graduation in Automobile Engineering. He loves to lead a free life, so he left his job & started blogging. Now, he does research on every automotive problem, parts & products and seeks a better solution & best products & shares his findings with his readers to help them as well as to minimize their struggle.