heater control issue - Page 2 - Chevy Impala Forums
Chevy Impala 7th Gen Discussion W-Body 2000-2005. Discuss all Chevy Impala 7th Generation Performance and Technical Discussion here.

User Tag List

 8Likes
Reply
 
LinkBack Thread Tools Display Modes
post #16 of (permalink) Old 10-16-2019
Senior Member
 
mdubyk's Avatar
 
Join Date: Feb 2018
Location: Atlanta, GA
Posts: 110
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 29 Post(s)
Thanks: 2
Thanked 9 Times in 9 Posts
Garage
There's a vacuum reservoir tank attached to the back of the HVAC control module. Check it and the lines to the control head for vacuum.
mdubyk is offline  
Sponsored Links
Advertisement
 
post #17 of (permalink) Old 10-30-2019
Senior Member
 
mdubyk's Avatar
 
Join Date: Feb 2018
Location: Atlanta, GA
Posts: 110
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 29 Post(s)
Thanks: 2
Thanked 9 Times in 9 Posts
Garage
Quote:
Originally Posted by My 2003 Impala View Post
Quote:
Originally Posted by mdubyk View Post
2 things to look at:

Is vacuum present at the back of the HVAC control head?

Does the mode knob actually rotate the vacuum switch on the back of the HVAC control head?

I will check it over and see
What did you find?
mdubyk is offline  
post #18 of (permalink) Old 4 Weeks Ago Thread Starter
Junior Member
 
My 2003 Impala's Avatar
 
Join Date: Jul 2019
Posts: 28
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 15 Post(s)
Thanks: 0
Thanked 0 Times in 0 Posts
Haven't had much time to look at it deeper, trying to figure out how to remove the trim panel without breaking it
My 2003 Impala is offline  
Sponsored Links
Advertisement
 
post #19 of (permalink) Old 2 Weeks Ago Thread Starter
Junior Member
 
My 2003 Impala's Avatar
 
Join Date: Jul 2019
Posts: 28
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 15 Post(s)
Thanks: 0
Thanked 0 Times in 0 Posts
Update: Was looking deeper under hood yesterday and found a vacuum line broken. I slipped a piece of hose over it, and now the mode selector works. Just have to fix the blower speed switch as it only works on positions 4 and 5
plano-doug and sheila like this.
My 2003 Impala is offline  
post #20 of (permalink) Old 2 Weeks Ago
Senior Member
 
plano-doug's Avatar
 
Join Date: Aug 2009
Location: Plano, Texas
Posts: 2,622
Mentioned: 6 Post(s)
Tagged: 0 Thread(s)
Quoted: 382 Post(s)
Thanks: 131
Thanked 380 Times in 355 Posts
Quote:
Originally Posted by My 2003 Impala View Post
Update: Was looking deeper under hood yesterday and found a vacuum line broken. I slipped a piece of hose over it, and now the mode selector works. Just have to fix the blower speed switch as it only works on positions 4 and 5
Kudos on fixing the vacuum leak.

The speed control issue is usually what's called the blower motor resistor. In some cases, they actually contain resistors; in other cases, it contains a more sophisticated electronic circuit for controlling the fan motor speed. Either way, as long as you get a "blower motor resistor", you should be fine.

Looking on Autozone's website, most of them are around 40 bucks, but there are two outliers: one at 12 bucks and another at 94.

The resistor is located near the fan, up above the passenger's feet, against the firewall.

HTH.

Doug

.
plano-doug is online now  
post #21 of (permalink) Old 2 Weeks Ago Thread Starter
Junior Member
 
My 2003 Impala's Avatar
 
Join Date: Jul 2019
Posts: 28
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 15 Post(s)
Thanks: 0
Thanked 0 Times in 0 Posts
Quote:
Originally Posted by plano-doug View Post
Kudos on fixing the vacuum leak.

The speed control issue is usually what's called the blower motor resistor. In some cases, they actually contain resistors; in other cases, it contains a more sophisticated electronic circuit for controlling the fan motor speed. Either way, as long as you get a "blower motor resistor", you should be fine.

Looking on Autozone's website, most of them are around 40 bucks, but there are two outliers: one at 12 bucks and another at 94.

The resistor is located near the fan, up above the passenger's feet, against the firewall.

HTH.

Doug

.

Thanks I'll check those out. Fan speeds 1,2,3 are dead, fan only comes on in 4 and 5
My 2003 Impala is offline  
post #22 of (permalink) Old 2 Weeks Ago
Senior Member
 
plano-doug's Avatar
 
Join Date: Aug 2009
Location: Plano, Texas
Posts: 2,622
Mentioned: 6 Post(s)
Tagged: 0 Thread(s)
Quoted: 382 Post(s)
Thanks: 131
Thanked 380 Times in 355 Posts
Quote:
Originally Posted by My 2003 Impala View Post
Thanks I'll check those out. Fan speeds 1,2,3 are dead, fan only comes on in 4 and 5
I think it's almost always the resistor. I can't recall anyone with a bad speed switch.

Seems like fan speed control is a problem that goes way back. I've done at least one resistor on one of my Impalas. And my dad's 64 Chrysler had similar issues with its A/C fan, too

Doug

.
plano-doug is online now  
post #23 of (permalink) Old 2 Weeks Ago
Senior Member
 
sheila's Avatar
 
Join Date: Sep 2013
Posts: 1,859
Mentioned: 5 Post(s)
Tagged: 0 Thread(s)
Quoted: 194 Post(s)
Thanks: 315
Thanked 326 Times in 261 Posts
^+1. Again, on my old Fords, underhood vacuum breaks/leaks were common. Think age and engine heat/cold. Also, with a faulty/burnt blower motor resistor, blower fan only worked on high speed(s). Mode (vent) selection was controlled by vacuum, temperature was controlled electrically via the temp blend door actuator motor.
sheila is online now  
post #24 of (permalink) Old 2 Weeks Ago
Junior Member
 
gcrawdad's Avatar
 
Join Date: Feb 2018
Posts: 28
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Thanks: 0
Thanked 2 Times in 2 Posts
My leak was in the thin black vacuum line from the manifold. It was in the area below the fuse/relay boxes.
sheila likes this.

Just the facts maam
gcrawdad is offline  
Sponsored Links
Advertisement
 
Reply


Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Chevy Impala 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:
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:
OR

Log-in










Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode



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 On
Pingbacks are On
Refbacks are On

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