AC issue

[Robbann]

I recently bought a 2020 Corolla Hybrid and have mixed feelings about it. Overall, the car is really nice, but there's an issue with the AC/fan that's been bothering me.

When the ac is on, there's an intermittent electric buzzing sound coming from the fan. It sounds similar to an old refrigerator. Sometimes the sound is quite noticeable, while other times it's quiet. This inconsistency is puzzling and somewhat frustrating.

The noise seems to be more frequent and noticeable when it's hot outside, probably because the AC is working harder. However, even then, it's not constant - it comes and goes.

Has anyone else experienced this with their Corolla Hybrid? I'm wondering if this is a common issue or if there might be something wrong with my particular vehicle. 

[TonyHSD]

3 hours ago, Robbann said:

I recently bought a 2020 Corolla Hybrid and have mixed feelings about it. Overall, the car is really nice, but there's an issue with the AC/fan that's been bothering me.

When the ac is on, there's an intermittent electric buzzing sound coming from the fan. It sounds similar to an old refrigerator. Sometimes the sound is quite noticeable, while other times it's quiet. This inconsistency is puzzling and somewhat frustrating.

The noise seems to be more frequent and noticeable when it's hot outside, probably because the AC is working harder. However, even then, it's not constant - it comes and goes.

Has anyone else experienced this with their Corolla Hybrid? I'm wondering if this is a common issue or if there might be something wrong with my particular vehicle. 

Hi, 

I can assure you that absolutely every Toyota hybrid owner has experience exactly the same buzzing sound from the ac compressor and it is not constant but in and off . This is how these cars work. There is nothing to worry about and it’s not strange . All cars with ac acts the same however in normal petrol or diesel cars these ac compressor ans fan noises are dampen by the noise of the engine. 👍

[2badmice]

Tony, are you sure?

I do not recall any buzzing in the last 3 years with mine.

Can you send a video?

[TonyHSD]

1 hour ago, 2badmice said:

Tony, are you sure?

I do not recall any buzzing in the last 3 years with mine.

Can you send a video?

I am positive. 
The buzzing sound is coming from the electric air conditioner compressor.
The  loudness and density depends on outside air temperature, sun shines and interior temperature settings on hvac system. In hot sunny days it is loud in the first few minutes then after not so loud but still present on every start up of the car from 0-40C° , in negative cold like -4C° or below the ac will not start so no buzzing sound.
The on and off sound of the compressor is accompanied by radiator fans which may make it less pronounced. 
Buzzing sound when too loud can be also a sign of low gas and low oil content in the system. Ac service highly recommended in this case. 
Here a video just taken of my car 

 

[Red_Corolla]

Never heard it on mine, but I don't drive in silence. Always have the radio on, or a podcast, or something. Even so, I can still hear sounds if they're intrusive, and I don't hear a peep from the A/C.

[Mr Billiards]

10 hours ago, TonyHSD said:

I am positive. 
The buzzing sound is coming from the electric air conditioner compressor.
The  loudness and density depends on outside air temperature, sun shines and interior temperature settings on hvac system. In hot sunny days it is loud in the first few minutes then after not so loud but still present on every start up of the car from 0-40C° , in negative cold like -4C° or below the ac will not start so no buzzing sound.
The on and off sound of the compressor is accompanied by radiator fans which may make it less pronounced. 
Buzzing sound when too loud can be also a sign of low gas and low oil content in the system. Ac service highly recommended in this case. 
Here a video just taken of my car 

 

IMG_8598.MOV

My 2023 2ltr GR Sport makes the same noise, never given it a thought really, just use the car.

[fred88]

11 hours ago, Red_Corolla said:

Never heard it on mine, but I don't drive in silence. Always have the radio on, or a podcast, or something. Even so, I can still hear sounds if they're intrusive, and I don't hear a peep from the A/C.

Nor me.

[AndrueC]

I've never heard it from my 2019 Corolla either. Not from inside the cabin at least. No idea if it can be heard from the outside but don't really care 🙂

Then again I do usually have music playing (not loudly).

[TonyHSD]

I can assure you that they all does that noise if you have hvac settings same as me and you actually should, because this is the best way to have comfort in the cabin and extend life of your hybrid Battery. 

AC - ON

Auto - ON

Temperature - 22C° Or whatever you like and recirculating off - this the car will maintain as needed 

Eco - off 

Open door or window and on the first start in the morning or after at least an hour after your last journey. 

If you have different settings on hvac, if AC is off, if auto is off, if fan is off, or you have restart the car after 10-15 min since you have stopped the buzzing noise is less pronounced.
And my door was open to record the video. 
You probably haven’t heard the flaps are moving in the dashboard long after you have turn off the car because you most likely never sat in for long .
Well I spent 12hrs in this car every night , it’s my work place and so I had a chance to hear and see things. 👍 

[2badmice]

On 8/15/2024 at 10:24 PM, TonyHSD said:

I am positive. 
The buzzing sound is coming from the electric air conditioner compressor.
The  loudness and density depends on outside air temperature, sun shines and interior temperature settings on hvac system. In hot sunny days it is loud in the first few minutes then after not so loud but still present on every start up of the car from 0-40C° , in negative cold like -4C° or below the ac will not start so no buzzing sound.
The on and off sound of the compressor is accompanied by radiator fans which may make it less pronounced. 
Buzzing sound when too loud can be also a sign of low gas and low oil content in the system. Ac service highly recommended in this case. 
Here a video just taken of my car 

 

IMG_8598.MOV

Nothing of the sort in my car since 2021, I always have the aircon running and change the temperature accordingly to my own comfort needs

 

Appreciate you showing me this, I will have a dabble with other Toyota's that come in to work and see if I can spot if there's a trend with certain variants, models or years.

 

Cheers

[TonyHSD]

5 hours ago, 2badmice said:

Nothing of the sort in my car since 2021, I always have the aircon running and change the temperature accordingly to my own comfort needs

 

Appreciate you showing me this, I will have a dabble with other Toyota's that come in to work and see if I can spot if there's a trend with certain variants, models or years.

 

Cheers

You are welcome. 
This noise is definitely normal and happens to all Toyota hybrids since 2010- now with electric air conditioning compressor. 
To here it there need to be specific conditions, in others it will not happen or will not be so loud and it may trick you that it is not there. 
Same like the noise from the electric brake booster pump, presented at the very beginning of the video. 👌

[AisinW]

The high voltage AC has winning and high pitch sound.  it is normal in all hybrid and EV. 

[yossarian247]

I've noticed that the harder I work the aircon the noisier the compressor becomes, which makes sense really. Eg If the car has been parked in direct sun on a scorching hot day, then I get in and set the climate control to a low temperature the compressor is really noticeably noisy for the first few minutes. However, on a mild or cold day with the controls set to 20c for example I don't hear anything at all. Its the same in both our Corolla and C-HR. 

[fred88]

I'm sure you're right, in fact I'm sure I've read that in those circumstances you should let the windows right down for a few minutes to let some of the heat escape rather than leave the aircon to do it.

[TonyHSD]

There is also an option to reduce noise and most likely the performance of the ac compressor via Carista app. 
If anyone has that obd  adapter can check for themselves. 

[AisinW]

The AC noise is like a generator but in a very hot day 35C, it sounds much louder mid tone. I found that the AC is very efficient and get cold really fast. Faster than Golf or Astra for the same size car. 

Mine is just over 100k miles and never do any service, besides cabin filter yearly. It blows ice cold even during 35C heat wave season. 

There is no exact maintenance schedule for AC as long as it blows cold air. The exact easiest test is using termometer sticks to the air vent and see if it is still within range in the manual handbook. 

[Trewithy]

2 hours ago, AisinW said:

The AC noise is like a generator but in a very hot day 35C, it sounds much louder mid tone. I found that the AC is very efficient and get cold really fast. Faster than Golf or Astra for the same size car. 

Mine is just over 100k miles and never do any service, besides cabin filter yearly. It blows ice cold even during 35C heat wave season. 

There is no exact maintenance schedule for AC as long as it blows cold air. The exact easiest test is using termometer sticks to the air vent and see if it is still within range in the manual handbook. 

What is the figure quoted in the handbook?

[AisinW]

I cannot find it yet but generally 15C below the ambient temp is pretty good rule of tumb. 

If the AC is still cool, it still works fine. There always some% of refrigerant leak over time from the joints but generally, 12-15y is typically a good time to do evacuate and refill by certified hybrid/EV AC service. 

[TonyHSD]

3 hours ago, Trewithy said:

What is the figure quoted in the handbook?

AC ON 

Recirculating off

Temperature set to low

Fan speed manual control position 3

Air flow middle of the dashboard

You are looking for 4-8C° for properly working ac.