Honda Pilot AC Noise: Top 6 Noises, Causes & Fixes!

A Honda Pilot will get noisy when something’s up! We’ve already addressed the various noises it can make when accelerating and turning the steering wheel. In this article we’ll tackle the troublesome noises that can sometimes be heard when the air conditioner is on.

There are different types of noises that can occur, pointing to their respective underlying causes. We’ll address the most common ones in this article so you can diagnose and fix your particular issue sooner rather than later.

1. Hissing Noise

A hissing sound can occur for two reasons – the AC is running low on gas (also known as coolant or refrigerant) or there is a gas leak somewhere in the system.

If it’s running low on gas you will also notice that the cooling is not as efficient as before. One fan might blow colder and other warmer air. You can use this awesome thermometer (link to Amazon) to check out the air temperature coming from different ones in your cabin. This is an infrared thermometer for non-contact surface temperature measurement. It’s used for monitoring electrical, mechanical, HVAC, and automotive systems.

If there’s a big temperature difference between the vents (it can be 10-20 degrees in some cases), that’s a sign that you need to add some coolant into the system. You can do so following these steps:

• The car should be running
• Open the hood and find the low pressure valve
• Plug in the AC Refrigerant Recharge Kit with Hose and Gauge (link to Amazon) on the low pressure valve to fill it up
• There is an indicator on the kit that shows the amount of pressure. Once it’s adequately filled, you can turn off the car and unplug the kit. But before you do so, you can take the thermometer again and check the temperature of the air blowing from the fans. It the problem was a lack of coolant, the air temperature should now be about the same.

Here is a video demonstration of these steps:

2. Squeaking noise

This is typically caused by lack of lubricant, dust and other particles. You will find two blower motors, one on the front and one on the back.

One on the front is located under the glove compartment.

• Unscrew the cap, pull it down and pop open the next bit of plastic with a flat screw driver to access the motor
• Now, use canned air through the hole to blow out dust from the bearing
• Next, use a gel lubricant like WD-40 on the same area to lubricate the bearing
• Now turn it on to test if the noise is still present
• If the noise is gone, put all the parts back in their place and screw them tight

Note that the process might not be exactly the same for every Honda Pilot model because the parts can somewhat differ. But the general idea is the same – remove dust and dirt and lubricate.

Here is a video demonstrating these steps:

3. Clicking Noise

This noise can mean two things:

• It might simply be an indicator that the AC clutch is activating. In that case it’s not a problem.
• It can also happen if there is an obstruction in a duct or fan. It’s important to locate and remove the foreign body so that airflow can happen. Otherwise there is a risk of overheating.

If your AC is otherwise working just fine, it’s likely that it’s just the sound of the AC clutch activating. If you’re worried, check the ducts/fans for foreign bodies, including the air inlets at the top of the hood.

4. Whistling or Humming Noise

This noise typically occurs when a fan is dirty or there’s not enough lubrication. To examine the issue you will need to open the ventilation circuit. Then you can see if the fan is properly adjusted.

If there’s any damage, it might require a replacement. But if nothing is damaged, you can just clean it and/or lubricate it and see if it gets rid of the noise before putting it back in.

Here’s a video showing how to access a fan and fix it on your own. This guy found a leaf (!) and a lot of dirt in there. Once he removed it the humming noise was GONE for good:

5. Slamming Noise

Slamming noise can occur on the AC side of heater fans, and the typical cause is an issue with the AC compressor clutch or the compressor itself. One or more parts might have dislocated or misaligned and are hitting against other parts, causing the slamming noise to occur. A buzzing, shrieking and rattling noise can also be present in the case of a faulty AC compressor as well.

6. Grinding Noise

Grinding noise is common when starting the Honda Pilot with the AC on. It’s typically due to liquid migration. The compressor is forced to compress a small amount of liquid and that’s what’s causing the grinding noise. It’s pretty common and doesn’t seem to be causing any real issues. It can be prevented by turning off the AC when starting the car.

Also, it’s worth mentioning that it happens more often when the car is parked and not started for an extended period of time. Starting it every day can prevent the noise from happening.

Final Thoughts

I hope you’ve found these tips helpful. If you’re not a DIY kinda guy, you can always drive your Honda Pilot to a mechanic and get him to check it out for you. But oftentimes it’s a minor issue that you can fix by yourself and save some money in the process.