Blend Door Actuator Symptoms

Blend Door Actuator Symptoms and Replacement Cost

The blend door actuator is probably something you’ve never heard of in a car. However, it’s actually quite an important part of your car’s air-conditioning system. Once the blend door actuator fails, you will notice symptoms with your car. Blend door actuator problems won’t prohibit you from driving, but they can make life inside the car uncomfortable. We’ll list down the blend door actuator symptoms below and you can see if your car has any of the symptoms. If it does, you may need to replace it, and we’ll be discussing the replacement cost and how to do it yourself as well.

What’s a Blend Door Actuator?

Okay, so what exactly is a blend door actuator? Well, the blend door is what controls the direction of the airflow in your car’s air-conditioning system. The actuator is basically just another word for ‘motor’, so it’s a motor that controls the blend door. It’s basically a small electric motor that has sensors that are connected to your car’s air-conditioning system. The blend door actuator takes the shape of a small plastic box with a wire connector attached to it. Within it lies several gears and an electronic system that controls the motor.

When you adjust the settings in your A/C system, such as the temperature and the airflow, the signals will go through the actuator. Then the actuator will adjust the blend door accordingly. Most cars will have either one or two actuators, but your car may have more of them if it has the ability to control the temperature in different zones or multi-zone climate control as carmakers often say.

The blend door is controlled by the actuator, and it’s the system that diverts and controls the airflow. Why is it called a blend door? Well, it’s because it’s really just a flat plastic panel that looks like a door. Under the command of the actuator, the door will open and close to divert airflow depending on how you set it. It’s about as low-tech as you get in a car.

You can learn more about the workings of a blend door actuator in the video below. It also explains why some Fords have frequent failures with this component:

Bad Blend Door Actuator Symptoms

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When the blend door actuator goes bad, you will notice several things in your car. They’re usually not a big deal and won’t prohibit you from driving, but it can be annoying. Some of these symptoms may not be caused by the blend door actuator since the air-conditioning system has several components and any of them can cause this. That being said, here are faulty blend door actuator symptoms:

Noises from the Dashboard Area

As mentioned, the blend door actuator has several gears inside to operate the blend doors. At some point, these gears are bound to fail. If anything, they’re more prone to failure since they are plastic gears rather than metal. When some of the teeth have worn down or broken off, they will start slipping and grind excessively against each other, which creates noise.

This noise usually happens when you turn on the air-conditioning system and make adjustments to the settings. It will usually make either a droning or squeaking noise. Try to listen to where the noise is coming from. If it comes from the central dashboard area or the area where you control the A/C system, there’s a good chance that the blend door actuator is causing this.

Knocking or Clicking Noise from Dashboard

This noise usually comes when you turn the ignition on in your car. In most cars, the blend door actuator will recalibrate the position of the door every time you turn on the ignition. If the position that the control head (your A/C control) is asking for does not correlate with the actual position of the door, it will make this clicking noise as it tries to readjust it. Broken teeth in one of the gears can also cause this noise. So, if you hear a knocking or clicking noise from your dashboard when you turn the car on, you may have a blend door actuator problem.

Keep in mind that a faulty relay may cause this noise. A blend door recalibration may also help to solve the problem, we’ll teach you how to do this later on.

Inconsistent Airflow

Since the blend door is what controls and diverts the airflow in your car’s air-conditioning system, inconsistent airflow is a good indication that you have a blend door actuator problem. For example, if your car suddenly diverts airflow to an area (such as the footwell) even though you didn’t ask for it to do so, then there’s a good chance you have a problem with the blend door actuator.

Additionally, there are only two things that can go wrong with the blend door actuator: either there’s damage to the gear or the motor/actuator has burnt out. As mentioned, the broken gear will create droning noises. You can actually get away by just replacing the gear in the actuator, but we recommend replacing the entire unit altogether since it’s easier. As for when the motor has burnt out, you will likely be unable to control the temperature settings. If you adjust the temperature and it doesn’t seem to change, you likely have a burnt-out circuit. Either way, you’ll need to replace the blend door actuator.

Diagnosing the Blend Door Actuator

As mentioned, a faulty relay may cause the clicking noise you hear when you turn the ignition on. A blend door recalibration may also help eliminate the problem and you won’t need to replace the entire actuator. We recommend recalibrating the blend door first and then checking the relay. If either of these methods fixes the problem, then you won’t need to replace the blend door actuator.

Blend Door Recalibration

The process for a blend door recalibration may differ depending on the car’s make and model. We recommend checking your owner’s manual or with online owner’s forums to find the correct procedure for your car. But in general, here’s what the process typically involves:

  1. Turn the ignition on.
  2. Turn on the ‘Auto’ setting on your car’s air-conditioning system.
  3. Switch off the ignition.
  4. Remove the air-conditioning fuse for 1 minute.
  5. Turn the ignition back on and leave it be for 2 minutes. This puts the system in relearn mode.
  6. After 2 minutes, turn it off and then on again. Leave the ignition for 15 seconds. See if the problem persists.

Again, your car may have a different procedure for recalibrating the blend door. So you will have to research the procedure for your car. However, the method above usually works for GM vehicles, and the process for other cars is usually quite similar. If the problem persists, then you will need to check the relay:

Diagnosing a Faulty Relay

A relay is basically an electrically operated switch. Sending power through the controls of the relay will magnetize it and makes a copper contact point to close which powers up whatever device needs the electrical power. Think of it as a light switch that you operate by using the knobs and switches in your car.

During operation, the relay makes an audible click as the contact point opens and closes, which is perfectly normal. However, a faulty relay or dirty contact points may cause the relay to engage and disengage quickly. In turn, this makes the repeating clicking sound you might be hearing.

To test the relay, you will need to locate it and remove it (check your owner’s manual to find the air-conditioning relay). Afterward, you will need a multimeter to test the relay. Here’s how to diagnose a relay:

You can also try shaking the relay after you pull it out. If it makes a rattling noise inside, this is a good indication that you have a bad relay. If you have a bad relay, simply replace it with a new one. A relay should be no more than $15 to purchase, but be sure to purchase the correct relay.

Blend Door Actuator Replacement Cost

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When you notice the blend door actuator symptoms above and verified that the problem is indeed the actuator, you will need to replace them. The blend door actuator usually costs between $100 – $300 depending on the car’s make and model, before labor costs. On average you can expect to pay around $150 for the actuator itself. As an example, the blend door actuator for a 2006 Toyota Camry is $225 according to Toyota’s website. Factor in the labor cost, you’re looking at a total of around $375 to replace a Toyota Camry’s blend door actuator.

Replacing the blend door actuator is actually a fairly simple process, and it should take no more than an hour. So the labor will cost you around $75 – $150 depending on labor rates at your local repair shop. In general, you can expect the total cost to be no more than $400.

As for luxury and performance cars, they shouldn’t cost that much more. The actuator isn’t a performance-affecting part so they are generally similar across all cars. However, if your car has multi-zone climate control, then your car has more than one actuator in the air-conditioning system. If they fail simultaneously, then you will need to replace all of them. In which case, the replacement cost will double.

Saving Money on Blend Door Actuator Replacement

We all like to save money when possible, especially when it comes to car part replacements. When it comes to the blend door actuator, there are two ways you can save a bit of cash: either you get a cheaper non-OEM (Original Equipment Manufacturer) or aftermarket part. Or you can do the job yourself to save on labor costs. Or do both if you want to save even more money.

Buying Non-OEM Blend Door Actuator

Much like other components in a car, there are third-party manufacturers out there that make blend door actuators for your car. Autozone for example has a lot of third-party blend door actuators on stock, and they can be as cheap as $25. However, keep in mind that you will need to make sure that the part you’re buying fits your car. Otherwise, it won’t work and you’re going to have to buy another one that actually fits. So be sure to check if the part fits your vehicle. Also, if it turns out that the non-OEM part is just as expensive as the OEM part, then you’re better off buying OEM anyway.

Additionally, we always like to remind you to be wary when buying aftermarket or non-OEM parts. They’re not always bad, and sometimes they’re cheaper because they don’t charge a colossal mark-up as carmakers do. But often they are cheaper because they are lower in quality. We suggest that you read customer reviews before buying, make sure that customers who have previously bought the product are happy with it.

Also, you should buy non-OEM products that have a warranty whenever possible. So if the part fails prematurely, you can replace it for little to no money at all.

Replacing Blend Door Actuator Yourself

If you don’t want to buy aftermarket parts and prefer to buy OEM for peace of mind, then you can save money by replacing the blend door actuator yourself. This is a good way to save money because replacing the blend door actuator is a fairly simple job and with the right tools you can do it yourself. It should take no more than an hour of your time to do this job. Here’s how to replace the blend door actuator yourself:

Steps to Replacing the Blend Door Actuator

  1. Remove the dash panel covering the blend door actuator. Check with the owner’s manual to see where it’s located, and then remove the dashboard cover. More often than not it’s usually located at the lower dash panel or glove box. You will usually need a small socket and ratchet to remove the screws that are holding the panel in place.
  2. Remove the actuator’s wiring connector. There might be a safety clip that holds it which you will need to undo carefully using a flathead screwdriver. Be gentle as they can break quite easily.
  3. Remove the actuator by removing the screws that hold the actuator in place. You can do this by using a socket and ratchet, but the sizes will vary depending on the car.
  4. Before installing the new actuator, make sure nothing is obstructing the air door. Manually turn them back and forth in full travel to make sure there’s no obstruction since it can damage the new actuator. There’s a good chance it caused the old actuator to fail in the first place.
  5. Once you’ve ensured that there’s no obstruction, you can now install the new blend door actuator. Simply put it in place and tighten the screws back on.
  6. After the screws are in place, reinstall the wiring connector. You should hear a click when it’s installed.
  7. Once done, recheck if you’ve done it properly by turning on the car and the air-conditioning system.
  8. Reinstall the dash cover once you’re done.

You can watch the video below to learn more on how to replace the blend door actuator yourself. The video below actually shows how Oz Mechanic replaces the gears inside the old actuator and putting it back in, but it will give you good visual instruction on how to remove and install a new actuator:

Questions & Answers

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Can I Drive with a Bad Blend Door Actuator?

You can. The blend door actuator doesn’t affect your car’s performance or safety, so you can definitely drive with a bad blend door actuator. However, you might notice your air-conditioning system not working properly. The air temperature that it’s blowing might not be correct and the car will either be too hot or too cold. Or it might divert air to areas where you don’t actually want it to be. This will be an inconvenience and driving will be uncomfortable. Your passengers might complain profusely at you for not fixing your car’s air-conditioning. Although that might be a good thing since they probably won’t want a free ride from you anymore.

In any case, yes you can drive without replacing your blend door actuator. But if you find it too uncomfortable, we recommend changing it.

How Long Do Blend Door Actuators Last?

There’s no telling how long a blend door actuator will last since carmakers don’t really specify their lifespan. However, it should last the car’s lifetime and it’s one of those car parts that rarely goes wrong. As an example, I’ve owned my 2011 Mitsubishi Outlander for 10 years and I’ve never had any problems with the blend door actuator. As long there are no manufacturer defects, it should last a long time and you don’t have to worry about it breaking anytime soon.

Keep in mind that an obstruction in the blend door may cause the blend door actuator gears to fail. This is because the obstruction will prevent the blend door from moving and it will make the plastic gears inside grind harder and the teeth may break off. Some common obstructions include pens, toothpicks, small toys, and bubble gums. If you have children, make sure they don’t insert anything into the air vents since it can obstruct the blend door.

Should I Replace It Myself?

If money is a bit tight at the moment, we recommend replacing it yourself to save some cash. As mentioned, it’s a fairly simple job and there’s little risk that you might break something else. However, if you’re not sure of your mechanical skills, we won’t blame you for spending that extra $150 on labor cost.

I’m Still Having Issues with My A/C, What Now?

If you see any of the blend door actuator symptoms we mentioned above, you likely have a blend door actuator problem. However, the car’s air-conditioning system is quite complex and something else might be causing your problem and you will need to check it.

For example, if your car’s air-conditioning suddenly starts blowing hot air even though the heater’s off, then that’s usually a sign of low refrigerant level. Or if you’re experiencing weak airflow, it’s often caused by a blower hose that has come loose, which causes air to not pass through the evaporator into the cabin. There might also be a problem with one of the seals in the system which has to remain closed. Also, remember to check the relay we mentioned earlier if you’re still hearing a clicking noise.

There are other issues as well that might be present, but most of them are rarely dangerous and repairs can wait if you can live with the inconvenience. However, one problem we wouldn’t ignore is when you smell gasoline coming out from your air vents. This indicates a gas leak and it would be wise to have the problem checked and fixed immediately since it’s dangerous for a variety of reasons.

You can learn more about car air-conditioning repair costs in an article we wrote here.


The blend door actuator is one of those car parts we rarely think or even know about. They’re not visible unless you open your dashboard and you don’t really notice it working because they work fine most of the time. As mentioned, blend door actuators usually last quite long as long as there are no manufacturer defects. This means you don’t have to worry about replacing them regularly and you won’t have to waste money on them.

If you notice any of the blend door actuator symptoms, be sure to follow our guide above on how to diagnose the problem. Sometimes the blend door just needs a recalibration or it’s just a faulty relay that costs no more than $15 to replace. But if it’s the blend door actuator, then be prepared to spend anywhere between $200 to $400 to replace them. You don’t have to replace them immediately, but we recommend doing so to keep life inside the car comfortable.

If you don’t want to spend money on labor costs, hopefully, our guide to buying aftermarket parts and replacing the blend door actuator yourself helps you to save some money. It’s a fairly simple job and it takes no more than a couple of hours to do at most.

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