1998 XJ sport - JeepForum.com

 
LinkBack Thread Tools
post #1 of 5 Old 01-21-2014, 08:40 AM Thread Starter
bootleg23
Registered User
 
Join Date: Nov 2010
Location: toronto
Posts: 11
1998 XJ sport

Hey guys,

Issue with my HVAC.

when i put the knob from floor to either wind shield defrost or a setting where the AC compressor turns on (another mystery to me, but that's for another thread) on full heat regardless of fan speed the Jeep will make a loud annoying buzzing noise that lasts for about 5-10 seconds, and here's the kicker, to those who think its the AC compressor bearing.

1. the noise still continues when the engine is OFF.
2. the AC compressor was replaced 20 months ago.

everything works as it should, blows heat fine, blows AC fine, all fan speeds work.

The belt was replaced with a goodyear gator about 16 months ago.

If the noise is still there when the engine is off what could it be, some relay thats not fully engaging or disengaging?

this only happens when its set to a setting when the AC is enabled, blowing on the floor it doesn't happen (blowing ONLY on floor doesn't engage the AC compressor)

any help appreciated.

bootleg23 is offline  
Sponsored Links
Advertisement
 
post #2 of 5 Old 01-21-2014, 10:41 AM
CCKen
Web Wheeler
 
CCKen's Avatar
1999 XJ Cherokee 
 
Join Date: Jul 2011
Location: Canton
Posts: 3,333
Quote:
Originally Posted by bootleg23 View Post
Hey guys,

Issue with my HVAC.

when i put the knob from floor to either wind shield defrost or a setting where the AC compressor turns on (another mystery to me, but that's for another thread) on full heat regardless of fan speed the Jeep will make a loud annoying buzzing noise that lasts for about 5-10 seconds, and here's the kicker, to those who think its the AC compressor bearing.

1. the noise still continues when the engine is OFF.
2. the AC compressor was replaced 20 months ago.

everything works as it should, blows heat fine, blows AC fine, all fan speeds work.

The belt was replaced with a goodyear gator about 16 months ago.

If the noise is still there when the engine is off what could it be, some relay thats not fully engaging or disengaging?

this only happens when its set to a setting when the AC is enabled, blowing on the floor it doesn't happen (blowing ONLY on floor doesn't engage the AC compressor)

any help appreciated.
The AC compressor will engage when Defrost or Mix (Windshield/Floor outlets) is selected and the outside temperature is above 30*F.

To see if you can find the buzzing noise after the engine is shut down you may want to roll down your glove box and poke you head close to the opening and see if you can hear the noise.

Here's a pic through the glove box opening. In view is the blower relay and the HVAC vacuum harness disconnect. To roll the glove box down just remove the 2 rubber stoppers and the glove box will hang down on its hinge.



If the noise seems to be furher down, remove the kick panel below the glove box. It's held on with 4 fatsteners. The top fastener holes are slotted so you don't have to remove the screws, just the botton 2. Listen around this area.

.
CCKen is offline  
post #3 of 5 Old 01-23-2014, 06:10 AM Thread Starter
bootleg23
Registered User
 
Join Date: Nov 2010
Location: toronto
Posts: 11
Ok thanks for the tip,

Ill go have a look when it warms up a bit, its -20 celsius out.

do you think its possibly that?

by very quickly listening when it happened it seems like it was coming from under the hood.

anyway ill report my finding in near future.
bootleg23 is offline  
post #4 of 5 Old 01-23-2014, 09:13 AM
CCKen
Web Wheeler
 
CCKen's Avatar
1999 XJ Cherokee 
 
Join Date: Jul 2011
Location: Canton
Posts: 3,333
Quote:
Originally Posted by bootleg23 View Post
Ok thanks for the tip,

Ill go have a look when it warms up a bit, its -20 celsius out.

do you think its possibly that?

Not necessarily. Just giving you some areas to check if you think the noise is coming from under the dash (HVAC related).

by very quickly listening when it happened it seems like it was coming from under the hood.

anyway ill report my finding in near future.
.
CCKen is offline  
post #5 of 5 Old 01-25-2014, 08:34 AM
tsc
Registered User
2006 LJ Wrangler 
 
Join Date: Mar 2007
Location: Pacific Northwest
Posts: 522
That right black block in your photo is a relay- unplug it and see if still does it- it could the relay vibrating.
tsc is offline  
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the JeepForum.com forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid e-mail address for yourself.



Email Address:
OR

Log-in









Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.




Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page



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 On
HTML code is Off
Trackbacks are Off
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome