Squealing from air conditioning - Acura MDX Forum : Acura MDX SUV Forums
Register Home Forums Active Topics Auto Loans Photo Gallery Search Today's Posts Mark Forums Read Auto EscrowInsurance
MDXers.org is the premier Acura MDX Forum on the internet. Registered Users do not see the above ads.
Reply
 
LinkBack Thread Tools Rate Thread
Old 10-05-2010, 12:31 PM   #1 (permalink)
Registered User
 
Join Date: May 2006
Location: East Coast
Posts: 6
Squealing from air conditioning

Has anyone heard of this happening? It's not too easy to explain, but I'll give it a shot.

Summary:
My air conditioning occasionally makes a loud squealing sound that doesn't stop until I shut off the air conditioning. If I turn it off for a few seconds and then turn it back on, the squealing stops. It is intermittent/occasional/random, which makes it almost impossible to troubleshoot.

Details:
  • My Car: 2005 MDX with Navigation Package, fully loaded with everything else.
  • Related Work: I recently had the 30,000 mile maintenance performed, in which they replaced the HEPA filters in the dashboard. I told them to check for anything that could be causing the squealing sound while they were in there. They didn't find anything. They sounded like they've never heard of the problem before.
  • The squealing seems to be coming from inside the dashboard. Not the engine compartment, the brakes, the steering wheel, or anywhere else.
  • The squealing sound usually happens in the morning.
  • The squealing sound usually happens when I am turning right. That is really weird to me.
  • The squealing sound is very loud. (Imagine someone screaming or shrieking in your car.) It happens suddenly which is very startling. It doesn't start at a lower volume and then increase; it starts loud and stays that way until you turn off the AC. It sounds like a police siren going off inside the car, but doesn't fluctuate in pitch like a police siren.
  • To make it stop, I have to turn off the air conditioning and then turn it back on.

It would be great to get this annoying problem fixed. I can only imagine the reaction of a passenger that isn't expecting it. It's like a horror movie where they play a loud sound when you aren't expecting it. I'd hate for the passenger to poop themselves in surprise.
2005MDXOwner is offline   Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
Old 10-05-2010, 12:45 PM   #2 (permalink)
Super Senior Member

 
SBM MDX's Avatar
 
Join Date: Feb 2009
Location: SF Bay Area
Posts: 1,087
Just to clarify –

When you say “turn off the A/C” do you mean A/C or Climate Control?

Also guess if the noise varied with fan speed you would have noticed?
__________________
'06 MDX
Touring/NAV/RES
midnightMDX’s ’01–’06 FAQs
SBM MDX is offline   Reply With Quote Quick reply to this message
Old 10-05-2010, 02:34 PM   #3 (permalink)
Registered User
 
Join Date: May 2006
Location: East Coast
Posts: 6
Hi SBM MDX, thanks for replying.

Quote:
Originally Posted by SBM MDX
When you say “turn off the A/C” do you mean A/C or Climate Control?
I'm not too good at the specific terminology, so I'll refer to the pictures in this thread. Take a look at the buttons at the top of the panel. I turn off the air conditioning by hitting the "OFF" button, and turn it back on with the "AUTO" button.

Quote:
Originally Posted by SBM MDX
Also guess if the noise varied with fan speed you would have noticed?
Unfortunately, I have not tried that yet. As soon as it happens I turn the AC off to make the awful sound stop. (When I'm in the middle of a turn and my car starts screaming bloody murder at me, my first thought isn't to fiddle around with it, just to make the screaming stop.) I'll try to remember to adjust the fan speed the next time it happens to see what happens.
2005MDXOwner is offline   Reply With Quote Quick reply to this message
Old 10-05-2010, 03:19 PM   #4 (permalink)
Registered User
 
Join Date: Sep 2004
Location: Florida
Posts: 4,355
My bet would be fan. That is the only moving part of your system that is inside the interior of your vehicle.

G
__________________
Happy Trails
2004 Black MDX Touring
G. COLTON is offline   Reply With Quote Quick reply to this message
Old 10-06-2010, 06:43 PM   #5 (permalink)
Super Senior Member

 
SBM MDX's Avatar
 
Join Date: Feb 2009
Location: SF Bay Area
Posts: 1,087
As G. suggested a most likely culprit is the fan motor.

Quote:
Originally Posted by 2005MDXOwner View Post
I turn off the air conditioning by hitting the "OFF" button, and turn it back on with the "AUTO" button.
OFF & AUTO invokes “Climate Control” which calls for heat & A/C as required dependant on the cabin temp selected.

In “AUTO” the fan is always on and varies from low to high. In “OFF” everything is off including the fan.

I don’t know if this motor uses bearings or bushings but dry bushings can scream then stop as described.
__________________
'06 MDX
Touring/NAV/RES
midnightMDX’s ’01–’06 FAQs
SBM MDX is offline   Reply With Quote Quick reply to this message
Old 10-08-2010, 07:48 AM   #6 (permalink)
Registered User
 
Join Date: May 2006
Location: East Coast
Posts: 6
Thanks to both of you for your help. I'll have the dealership replace the fan motor when I have it inspected in December.
2005MDXOwner is offline   Reply With Quote Quick reply to this message
Old 10-14-2010, 07:38 AM   #7 (permalink)
Registered User
 
Join Date: May 2006
Location: East Coast
Posts: 6
Quote:
Originally Posted by SBM MDX
Also guess if the noise varied with fan speed you would have noticed?
By the way, I finally had a chance to test this. Changing the speed of the fan after the noise starts up DOES change the pitch of the noise, although not by much. It changed the sound of the air blowing much more than the noise. The noise changed in pitch only slightly with each level adjustment up or down.
2005MDXOwner is offline   Reply With Quote Quick reply to this message
Old 10-14-2010, 11:56 AM   #8 (permalink)
Site Sponsor
 
hondacuraplanet's Avatar
 
Join Date: Jan 2001
Location: Buffalo NY
Posts: 4,996
Send a message via AIM to hondacuraplanet
I'm almost wondering if you don't have some debris in the ductwork. Either way, they'll know when you bring it in for sure
__________________
hondacuraplanet is offline   Reply With Quote Quick reply to this message
Old 10-15-2010, 01:44 PM   #9 (permalink)
Registered User
 
Join Date: May 2006
Location: East Coast
Posts: 6
Yeah, they were wondering that too when I told them about the problem. They said they'd look around while they were replacing the HEPA filters, but they said they didn't see anything. Maybe replacing the HEPA filters doesn't let them check the ductwork at the same time? I don't know.
2005MDXOwner is offline   Reply With Quote Quick reply to this message
Old 10-16-2010, 09:54 AM   #10 (permalink)
Registered User
 
Join Date: May 2010
Location: Katy, TX
Posts: 621
I haven't had this problem w/ my MDX, but have seen other blower motors begin to squeal. What causes this is worn bushings or loose bushing mount supporting the motor armature rotor. The wobbling allows the armature to contact the field magnets (solid magnets) which causes a spine-chilling squeal that is unbearable.

I've also seen same squeal on radiator fan motors for same reason. I disassembled and tried rebuilding one motor for the challenge, but was not able to find replacement bushings (oilite bearing/bushing). Further the bushing mounting may be part of the problem as it was very weak structurally.

good luck
TexasHonda is offline   Reply With Quote Quick reply to this message
Old 10-18-2010, 09:44 AM   #11 (permalink)
Registered User
 
Join Date: May 2006
Location: East Coast
Posts: 6
Thanks for the detail TexasHonda. And "spine-chilling" is a pretty good way of describing it.

Quote:
It's cold and dark at 6:30am when I get into my MDX. I close the door and the sounds of the world outside are replaced with a dead silence. I keep the radio off because I prefer the sound of my own thoughts in the morning. The air conditioning makes a soft whirring sound as it waits for heat. I back out of my driveway and begin traveling to work.

Stopped at a stop light, other vehicles silently slide up behind me like ghosts in the darkness. The light turns green, and I begin navigating a turn to the right. Without warning, a spine-chilling scream fills the interior of the car. I jump in my seat in shock and horror as the spectral hands of a banshee reach around from behind me...
OK, there isn't a banshee in my car, but it sure sounds like something horrible is screaming in there. Seriously, I wonder if someone with a heart condition might have problems with it.
2005MDXOwner is offline   Reply With Quote Quick reply to this message
Old 11-11-2010, 09:31 AM   #12 (permalink)
Registered User
 
Join Date: Nov 2010
Posts: 1
Hi Texas Honda/2005MDXOwner,
my 04 MDX has a similar issue. The screech appears to come from under the cup holders just behind the transmission. It occurs under braking, whether light or heavy. Do you know if there is a booster fan/blower motor for the a/c under there ? The bushing explanation seems to make sense, but before I go undoing stuff it would be good to know what is under there.
Brisbane MDX is offline   Reply With Quote Quick reply to this message
Old 11-11-2010, 09:44 AM   #13 (permalink)
Registered User
 
Join Date: Sep 2010
Posts: 34
Quote:
Originally Posted by Brisbane MDX View Post
Hi Texas Honda/2005MDXOwner,
my 04 MDX has a similar issue. The screech appears to come from under the cup holders just behind the transmission. It occurs under braking, whether light or heavy. Do you know if there is a booster fan/blower motor for the a/c under there ? The bushing explanation seems to make sense, but before I go undoing stuff it would be good to know what is under there.
My '01 did the same thing, I took the lower panel off the console on the passenger side to get to the fan motor. There is a plastic cover over the end of the fan motor, it is held on by three or four screws, I took off the cover and lubed the end of the motor shaft with a spray lube, just a small shot and it hasn't made the noise since. I'm thinking this is just a temporary fix, but it has been working fine for the last month and a half. You might also want to remove the lower panel on the drivers side and clean the screen, mine was caked solid, looked like a clothes dryer lint screen.
hurschel is offline   Reply With Quote Quick reply to this message
Old 11-12-2010, 09:03 AM   #14 (permalink)
Registered User
 
Join Date: May 2010
Location: Katy, TX
Posts: 621
One other possibility is the blower "squirrel cage" or fan is misaligned and contacting the housing. This might produce a similar sound to the armature striking the field magnets. However, it's certainly worth investigating to be sure this isn't the problem.

You may be ablel to view the fan cage by removing the cabin air filter.

I checked the procedure for blower replacement and it's not pretty. Major surgery requiring AC system discharge and evaporator removal. Ugly!

good luck
TexasHonda is offline   Reply With Quote Quick reply to this message
Old 12-19-2010, 05:37 PM   #15 (permalink)
Registered User
 
Join Date: Dec 2010
Posts: 1
"2005 MDX Owner" - Did you ever find out what the problem was? I have a 2005 MDX that has the exact same problem. It has been to the dealer repair shop three times and can't find anything wrong with it. I was hoping you might have a clue!
Thanks!
FriscoMDX is offline   Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
Reply


Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the Acura MDX Forum : Acura MDX SUV Forums forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
User Name:
If you do not want to register, fill this field only and the name will be used as user name for your post.
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:

Log-in

Random Question

Thread Tools
Rate This Thread
Rate This Thread:

Posting Rules
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is Off
HTML code is On
Trackbacks are On
Pingbacks are On
Refbacks are On



All times are GMT -4. The time now is 09:50 AM.



Powered by vBulletin® Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
SEO by vBSEO 3.3.2
Copyright 2000-2010 MDXers.org. All Rights Reserved.