a/c control issues 2005 TB

jaktomas1

Original poster
Member
Sep 11, 2012
7
I have a 2005 TB LT with electronic dual climate control. I have noticed some intermittent problems with mode and temperature control. I've been reading a bit on the Trailvoy forum and while there is some good if scary info it seems to deal mostly with models even older than mine. Is there a systematic method for diagnosing and addressing problems with the various actuator components in the system. Unlike most folks, my system seems to function properly in the a/c mode, but when heat is called for it is hit or miss what or where it will come from. Tks in advance.
 

The_Roadie

Lifetime VIP Donor
Member
Nov 19, 2011
9,957
Portland, OR
Welcome! This is the new clubhouse for discussing technical issues. Curious how you discovered us, since trailvoy attempts to censor any mention of the couple thousand "disloyal ones". :wink:

Anyway, it really takes a GM Tech II tool to take control of the HVAC control module and put each actuator through its paces. If you recently changed or discharged the battery, the lack of voltage to the control module memory forces each actuator through a recalibration process. That process is often stressful to older actuators and they get flaky or die.

Perhaps you've seen my main actuator location diagram:

allactuators-orig.jpg


There isn't much chance for actuators to interact unless the wiring has been chafed and shorting out at the back of the control module. Left and right temperature actuators are separate, but your issue sounds like confusion in the airflow mode actuator, that manages the airflow split between feet and center dashboard outlets. If you're in heat or AC mode, you can manually take control over the airflow mode and cycle it a few dozen times from feet to cehter dash. Ignore the defrost/windshield airflow because that's a separate actuator. If the actuator won't reliably move where you tell it to go, just swap it, is my recommendation. Only $33 on Amazon and you can check your own local parts stores.
 

jaktomas1

Original poster
Member
Sep 11, 2012
7
I was actually hoping to hear from you after reading your post on that OTHER forum. Of the five actuators in the system, which ones can be r&r without major dash disassembly?
 

The_Roadie

Lifetime VIP Donor
Member
Nov 19, 2011
9,957
Portland, OR
Who's "Rosie"? :confused: :frown:

All of them, if you call this a "minor" disassembly. It only takes about an hour to strip it down to this level:

dash03.jpg


Seriously, that's a slightly flawed question. You change actuators because they've failed. Not because they're the easier ones to change and you're shotgunning/guessing. Am I missing something?
 

jaktomas1

Original poster
Member
Sep 11, 2012
7
Sorry Roadie, I wasn't clear... Just looking at the diagram, not having gone beyond reading descriptions I was trying to plan ahead. Thanks for your help
 

LikeEnvoy

Member
Apr 17, 2012
128
Winnipeg, MB
I see references in other threads to the 'actuator positions diagram' but I can't find it. Then this thread has image names like "allactuators-orig.jpg" and "dash03.jpg" that have no actual images. Where are the images and diagram?
 

Mooseman

Moderator
Dec 4, 2011
25,257
Ottawa, ON
I see them. Those are the names of the files that are still hosted on roadie's personal site. I have uploaded them directly to this site in case of access problems.

allactuators-orig.jpgdash03.jpg
 

Mektek

Member
May 2, 2017
656
FL
There is a letter on each actuator denoting the type. You have to match the type - EG. if you want to replace an "S" actuator you have to put back another "S".
In my 02 the original was assembled with screws. The replacement "Woory" has plastic clips.
 

TJBaker57

Member
Aug 16, 2015
2,897
Colorado
Here is an example. The posted image lists 89018676 for drivers side defrost and temp actuator. That part number doesn't work for anything in a 2002 model year. Us 2002 owners need to be vigilant when getting parts!!

Screenshot_20211125-200036.pngScreenshot_20211208-102753.png
 
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TollKeeper

Supporting Donor
Member
Dec 3, 2011
8,047
Brighton, CO
@Mooseman - On part # 15-73596 - Is this part number the same regardless of auto or manual HVAC?

I see the cross reference part # is 604-110 Dorman.
Surprisingly, the ACDelco part is 5 bucks cheaper at Advance Auto. But its still north of 65 bucks!
AAP
Dorman: 69.99
ACDelco: 65.99

Amazon
ACDelco: 59.99
Dorman: 49.99

AutoZone is 64 ACDelco and 63 Dorman

Anyone have any better options? Budget friendly being the big one..
 

Mooseman

Moderator
Dec 4, 2011
25,257
Ottawa, ON
I think the actuators are the same. Just the way they're controlled is different.

We had a thread that had part numbers from International Trucks however, the links to the pics with the part numbers are dead. Maybe evilBay? I wouldn't use Dorman even for light bulbs. Probably Cheap Chinese Crap would be the same or better.
 

TollKeeper

Supporting Donor
Member
Dec 3, 2011
8,047
Brighton, CO
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