Jump to content

Blend Door Actuator Replacement


Recommended Posts

Posted

Hello

 

I have a 2006 Silverado with a bad blend door Actuator. It has been trouble shot at the dealership and this was the outcome. I tried the disconnect battery reboot several times with NO luck. The air will only blow thru the defrost which I hear is a default setting for when the door goes bad. I do want to install the new one myself. I just wanted to see if any of you have tried this and what has to be removed.

 

Thank you

Posted

Hi

Before you spend the $$ and time on a new actuator, try this actuator recalibration procedure. I had the same problem and it worked for me. This is a common problem after you disconnect the battery.

 

With the ignition switch in the on position, remove the HVAC/ECAS fuse for a minimum of 10 seconds. This fuse is located in the under hood fuse/relay box.

Re-install the HVAC/ECAS fuse.

Start the vehicle.

Wait 40 seconds for the HVAC control module to self-calibrate

 

Try this..... it SHOULD work

  • 4 months later...
Posted

I had the same problem on my 2001. I removed the actuator and found it was binding up when turned to the full hot postilion. What I found was the actuator servo was not factory calibrated correctly. There is a position potentiometer (pot) geared (blue) off of the output gear. It was off one tooth so that the servo would continue to try and drive the output gear past the stop on the case, causing the gear train to bind up. I carefully moved the blue position pot gear one tooth until the servo ran freely, stopping gently at each stop. It now seems to work fine.

 

I don't believe the heating system is tied to the computer on my 2001 LS at all. It does not have dual climate control.

 

WARNING:

Dissembling the servo (actuator) can result in loosing synchronization of the position pot, and if you are not familiar with servos, you may never get it working again.

 

Also, there is a GM bulletin about actuators that says not to apply power to a loose actuator. (I did a bunch of times with no problem, but consider your self warned, it may vary by year and trim level)

 

Scott

Posted

Good tips. Luckly I don't have this issue with my truck but it seems to be very common so I'm subscribing now for the day I need to go back to this thread to re read the procedure :thumbs:

Thanks

Posted

My 01 had the hot air sticking problem too Scott. A new actuator fixed it. I didn't know about what you described at the time so I just put a new one in. I might try that since my '02 is starting to stick now too.

  • 1 month later...
Posted
Hi

Before you spend the $$ and time on a new actuator, try this actuator recalibration procedure. I had the same problem and it worked for me. This is a common problem after you disconnect the battery.

 

With the ignition switch in the on position, remove the HVAC/ECAS fuse for a minimum of 10 seconds. This fuse is located in the under hood fuse/relay box.

Re-install the HVAC/ECAS fuse.

Start the vehicle.

Wait 40 seconds for the HVAC control module to self-calibrate

 

Try this..... it SHOULD work

Do you know id this will for the a 99? I can't find a HVAC/ECAS fuse in any of the fuse blocks.

Posted
Hi

Before you spend the $$ and time on a new actuator, try this actuator recalibration procedure. I had the same problem and it worked for me. This is a common problem after you disconnect the battery.

 

With the ignition switch in the on position, remove the HVAC/ECAS fuse for a minimum of 10 seconds. This fuse is located in the under hood fuse/relay box.

Re-install the HVAC/ECAS fuse.

Start the vehicle.

Wait 40 seconds for the HVAC control module to self-calibrate

 

Try this..... it SHOULD work

Do you know id this will for the a 99? I can't find a HVAC/ECAS fuse in any of the fuse blocks.

 

You can also disconnect the battery.

Posted
Hi

Before you spend the $$ and time on a new actuator, try this actuator recalibration procedure. I had the same problem and it worked for me. This is a common problem after you disconnect the battery.

 

With the ignition switch in the on position, remove the HVAC/ECAS fuse for a minimum of 10 seconds. This fuse is located in the under hood fuse/relay box.

Re-install the HVAC/ECAS fuse.

Start the vehicle.

Wait 40 seconds for the HVAC control module to self-calibrate

 

Try this..... it SHOULD work

Do you know id this will for the a 99? I can't find a HVAC/ECAS fuse in any of the fuse blocks.

 

You can also disconnect the battery.

 

I thought that is what causes the prolbem in the 1st place?

  • 2 months later...
Posted
Hi

Before you spend the $$ and time on a new actuator, try this actuator recalibration procedure. I had the same problem and it worked for me. This is a common problem after you disconnect the battery.

 

With the ignition switch in the on position, remove the HVAC/ECAS fuse for a minimum of 10 seconds. This fuse is located in the under hood fuse/relay box.

Re-install the HVAC/ECAS fuse.

Start the vehicle.

Wait 40 seconds for the HVAC control module to self-calibrate

 

Try this..... it SHOULD work

Do you know id this will for the a 99? I can't find a HVAC/ECAS fuse in any of the fuse blocks.

 

You can also disconnect the battery.

 

I thought that is what causes the prolbem in the 1st place?

 

 

 

alright, after trying to re-calibrate about a hundred times, i took the top cover off the actuator, flipped the gears so the cooling door would be open as i installed the actuator. it worked. skrew these chevy ac's. i am sick of waisting my bleeping time on nonsense.

Posted

I am also having a clicking noise from the passenger side heater actuator door. in recalibrating the actuators at what position would you put the dash controls to do the calibrations? Any help would be greatly appreciated.

 

thanks in advance,

  • 2 weeks later...
Posted
I am also having a clicking noise from the passenger side heater actuator door. in recalibrating the actuators at what position would you put the dash controls to do the calibrations? Any help would be greatly appreciated.

 

thanks in advance,

I have a 2003 Yukon XL Denali that had similar symptoms to those described in this thread. Air only blowing out the defrost vents and a very loud clicking noise coming from what seemed to be the instrument cluster. After reading dozens of forums, I realized the cause was the blend door actuator. This occurred immediately after starting the vehicle for the first time after replacing a headlight (replacing the drivers-side headlight requires removing the battery).

 

Somehow the blend door controller can get confused when the battery is removed and then re-installed. In my case, the controller kept the motor in the actuator running even after it hit up against the stop. There are several plastic gears inside the actuator and one of the teeth of the largest gear snapped off. This was the source of the clicking noise. While the cause is not clear, I will be implementing the reset steps after every battery removal to try to avoid this happening again.

 

A few notes on fixing the issue:

 

1) What the autoparts store described as the "Primary Actuator" is located directly above the gas pedal in a very tight spot. The kick panel just under the steering wheel is the first thing to remove. Take out the 2 screws on bottom. The top then theoretically pops off but mine took lots of pulling, prying and skin scraps to remove.

 

2) Next I removed a short vent pipe just above the brake pedal and then removed the electronic control module that was just above the vent pipe.

 

3) At this point and with some body contortions, I was able to see the actuator. It has 2 mounting screws (6mm). The bottom screw was easy to remove but the top was a bear due to obstructions. I was able to get at it using a flexible nut driver attachment.

 

4) Before removing the actuator, take a good look (maybe even a few pics) at the actuator arm that is attached to the actuator. Both have to be removed at the same time. The outer edge of the arm has 2 slots: The outer slot connect to a white geared arm that controls a flapper, while the inner slot connects over a black bump (which is essentially a cam that controls another flapper). Take note of how the gears of the actuator arm line up with the white arm.

 

5) It is a little tricky but you can work the actuator/actuator arm assembly out from under the dash.

 

6) The arm pulls straight off the actuator. Mine was a bit stuck and took a fair amount of encouragement.

 

7) I removed the 3 screws holding the cover on the actuator and noticed the broken teeth on the large sprocket. At the time, I did not realize the large sprocket only rotates about 1/4 of a revolution when in use. I could have tapped the sprocked off the metal spline, and then rotated the sprocket on the spline such that the broken teeth would be positioned outside the range of use. Not having yet realized this, I went to the parts store and bought a replacement for $140. Given this part fails regularly, they had them in stock.

 

8) Re-installing the actuator/actuator arm assembly was very challenging, particularly since I did not take the mental notes/pics as recommended above. Aligning the teeth on the 2 arms turned out to not be necessary. When the controller self-calibrates, the teeth line themselves up. The most important trick is to the both cams (one on the back side of the white toothed arm, and the other on the vent flapper assembly) in the slots of the actuator arm.

 

9) Be sure to do the calibration step (after connecting all wiring harnesses back, pull the 10A HVAC fuse in the box under the hood as described in this forum).

 

Much thanks to all those you have contributed to this forum. Replacing this part would have been much more challenging without all the posts.

Archived

This topic is now archived and is closed to further replies.

  • Recently Browsing   0 members

    • No registered users viewing this page.
  • Forum Statistics

    250.5k
    Total Topics
    2.7m
    Total Posts
  • Member Statistics

    342,902
    Total Members
    8,960
    Most Online
    whenindoubtuseahammer
    Newest Member
    whenindoubtuseahammer
    Joined
  • Who's Online   2 Members, 0 Anonymous, 381 Guests (See full list)

  • Latest Articles

  • Posts

    • Its no wonder you've gravitated to the oil types and brands you have in later years after trying certain brands and one being a specialty oil or at least very hard to come by up here and the other would have been a commonly found oil of the era and the vastly different outcomes as a result to using the vehicles in question the same distance for an OCI . It shows what marketing hype can do without actually having the product to back up the claims and that is no different now with the insane claims that are written on the side of a bottle of oil from some of the off the shelf oils.    What has surprised me and I was already finding this out before I bought my truck with the GDI engine, that this newer fancy technology that seemingly would suggest better fuel economy/emissions with this high pressure spray of fuel is not in reality kind at all to the engine or at least the oils life. Yet they insist on claiming long OCI with this technology just like they did with the port or similar type fuel injection systems when in reality its a step back in oil life to have a GDI system.    I think the mistake your making Grumpy is that your not sending your samples to Blackstone and getting the feel good glowing report that you can run it another 1000 or more miles and then send another sample where they say run it yet another 1000 miles and on and on it goes until your sending in something that looks a lot like road tar and then they may suggest you change your oil within the next 1000 miles 😆
    • I am guessing that engines of that design back then had a better ability to be abused and survive longer than a new design engine with the long timing chain and the overhead cams and phasers etc. But I would never guess that an engine could go that far and not fail spectacularly or at least die a slow death. 
    • In the 80's 90's I'd run Honda's 7,500 miles between changes using Red Line HP 5W20 and do it for hundreds of thousands of miles with issues. Back in the day it was an SAE 20 with the HTHS of a SAE 30 and SN add load. It was also very polar. Oxidation VOA was over 120. Besides those motors were SPFI and lean burn tech. I could have likely run it longer but never did.    We had a Toyota bought new I ran on Pennzoil's latest and greatest synthetic of the day with "Penthane". A made up word for a very low dose of PAO. Tried 7,500 mile OCI's in that Group III/VI chemistry and the rings tapped out at 90K. Rocker box wasn't as bad as the one Punch put up but it wasn't good either. Also a SPFI motor.    I'm around 3,750 across the board on these GDI monsters and the oil it tapped out by then usually on TBN/TAN crossover and color. Red Line HP Euro.    The AMSOIL SS brochures tell you to follow the OEM values for the service class but that it can be run up to 25K if monitored. I can't imagine what motor could go that distance and not tap out. I've never owned one.    Yes, I know. Lot's of people do. I'm just not going to be one of them. 
    • I knew a guy in the early 80's that bought a new Monte Carlo and ran it a 100,000 miles without ever changing the filter or the oil. Just kept adding. It looked like that inside.     
    • Good evening. I was lucky enough to get passed down to me a 2007 GMC LBZ that was my great uncle's. While the underside and rockers are more or less gone I feel like with time I can restore it to working order since it only has 110,000 miles and he put nearly every option he could get without getting the new body style since he did not trust DEF. So far I have done everything I can think of but when I put the key into the ignition nothing happens. I put 2 brand new batteries in it. Cleaned the terminals. Check all the fuses and relays and they all pass with my multimeter. I know I'm missing something that I just cant think of. The only odd thing is the OBD2 port works which makes me think its not the mega fuse. Any advice would be greatly appreciated. 
  • GM-Trucks.com Clubs

  • Popular Contributors

×
×
  • Create New...