Reindexing HVAC actuators....
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
Len
Once you install the actuators, just plug in the INTERIOR Temp Sensor and turn on the ignition and HVAC. Adjust the temp and observ the sensor shaft. As you adjust the temp, the sensor should follow.
Make sure that you clear the old DTCs.
BC
Once you install the actuators, just plug in the INTERIOR Temp Sensor and turn on the ignition and HVAC. Adjust the temp and observ the sensor shaft. As you adjust the temp, the sensor should follow.
Make sure that you clear the old DTCs.
BC
Heel & Toe
Joined: Apr 2010
Posts: 22
Likes: 1
From: Carthage Texas
What Bill said
Exactly! Also make sure when your checking the actuator's function that you turn the key to the on position and let the actuators cycle the blend doors through there range. Do that before you actually turn on the a/c. Is it very important that you do this step? I'm not sure, but I tend to err on the side of caution. Plus if there is any binding or cracking noises (worst case scenario) you should be able to hear it at this point. I your going after the passenger side actuator, remember to remove the glove box before trying to pull the pad off. Let us know how it goes!
8th Gear
Joined: Jul 2010
Posts: 8
Likes: 0
From: Houston Tx
First let me say this is a great resource and forum. I have never posted but have solved several problems with the answers from here.
My problem started after I worked on both window regulators. Got the windows working but my HVAC went crazy. It was working perfect before working on the windows.
I hear the actuators cycling the fan control does not work for minutes then will start but only on high which i was able to deal with but now I am getting hot air on the passenger side and cold on the drivers. I don't have a code reader and did try the #27 fuse recalibrate and the battery disconnect. still the same.
Pretty strange.
My problem started after I worked on both window regulators. Got the windows working but my HVAC went crazy. It was working perfect before working on the windows.
I hear the actuators cycling the fan control does not work for minutes then will start but only on high which i was able to deal with but now I am getting hot air on the passenger side and cold on the drivers. I don't have a code reader and did try the #27 fuse recalibrate and the battery disconnect. still the same.
Pretty strange.
Heel & Toe
Joined: Apr 2010
Posts: 22
Likes: 1
From: Carthage Texas
Code reader
You don't need a code reader because your car is already equipped with one. Do a search on diagnostics controls for the C5 (DIC). It pretty simple. I think its the following process.
Turn the key to the ON position, clear any messages, hold down the OPTION button, and press FUEL four times while still holding the OPTION button.
After that the computer should cycle through all the codes that your car is throwing/has thrown in the recent past.
As far as having problems with your HVAC, I'm at a loss considering all the gremlins your experiencing. I'm assuming it was working fine before you installed the new window regulators?
Turn the key to the ON position, clear any messages, hold down the OPTION button, and press FUEL four times while still holding the OPTION button.
After that the computer should cycle through all the codes that your car is throwing/has thrown in the recent past.
As far as having problems with your HVAC, I'm at a loss considering all the gremlins your experiencing. I'm assuming it was working fine before you installed the new window regulators?
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Melting Slicks
Joined: Sep 2006
Posts: 2,736
Likes: 7
From: Redding CA
Glad to help. This seems to be a common problem. The part also appears to be listed under AC/Delco #15-73044
http://froogle.google.com/froogle?q=...oogle&ct=title
Not exactly sure which model years use the "current service actuator" or the part number, but these can not be re-timed.
Your write up with photos is very detailed. I may be needing it if this problem returns. Thanks for the instructions.
http://froogle.google.com/froogle?q=...oogle&ct=title
Not exactly sure which model years use the "current service actuator" or the part number, but these can not be re-timed.
Your write up with photos is very detailed. I may be needing it if this problem returns. Thanks for the instructions.
Did anyone ever find out if this part number will work for sure on our C5's? It's listed as trailblazer/envoy/bravada but appears identical in pictures...
Thank you,
Donnie
Burning Brakes
Joined: May 2005
Posts: 956
Likes: 0
From: Philadelphia pa
Driver side hot from AC
This happened last year. I had some work done on the car and I assume they disconnected the battery and it started to blow hot air out the driver side vent. It was the end of the summer so I decided to wait and see what happened. At some point over the winter it fixed itself.
I had some work done on the car... I know they disconnected the battery and YET! Hot air again out the driver side. Should I disconnect the battery again and see if it resets itself?
Thanks
I had some work done on the car... I know they disconnected the battery and YET! Hot air again out the driver side. Should I disconnect the battery again and see if it resets itself?
Thanks
Melting Slicks
Joined: Sep 2006
Posts: 2,736
Likes: 7
From: Redding CA
Keyo,
YES!
Easy first. I'd disconnect it for a few seconds and try it...if the code is still there, disconnect it and re connect 3 or 4 times. Each time before you turn the key back OFF...turn the AC system completely off. Then disconnect, reconnect, turn key to on. Don't mess with the AC at all until it is done with the calibration...sometimes it takes like 30 seconds.
If you've got some crazy stereo or some settings you hate losing or are too lazy to write them down...pulling fuse number 27 should suffice to reset.
YES!
Easy first. I'd disconnect it for a few seconds and try it...if the code is still there, disconnect it and re connect 3 or 4 times. Each time before you turn the key back OFF...turn the AC system completely off. Then disconnect, reconnect, turn key to on. Don't mess with the AC at all until it is done with the calibration...sometimes it takes like 30 seconds.
If you've got some crazy stereo or some settings you hate losing or are too lazy to write them down...pulling fuse number 27 should suffice to reset.
Intermediate
Joined: May 2007
Posts: 29
Likes: 0
From: Wharton New Jersey
Hot air from driver side
Checked the forum. Read this post. Disconected the battery lead and when I hooked it up it worked like new. Has been working fine since. This is the second time that the forum has kept me from spending hundreds of dollars on problems that have a little at home fix. Thanks CF!
Just to recap my situation. I had to replace my HUD as TR3 blew and let out the magic smoke. After buttoning up everything and taking her for a test ride, I noticed I was getting hot A/C out of the driver side vents. There were no DTC's and the LH air mix door was only dropping 1/3 way down at the coldest setting. I followed the suggestions to reset all DTC's that were in memory even though none were generated for the A/C systems. I then set the passenger control to 12 O'clock and the driver control to 90 degrees. Disconnected the battery for 60+ seconds and reconnected. Turned ignition on and waited for the reindexing of the HVAC actuators. Started the engine and adjusted the temperature up and down. Both air mix doors were moving correctly again. Big relief!!
Pro
Joined: Apr 2008
Posts: 628
Likes: 4
From: Columbia SC
Finally got up the courage to read codes on my 8000-mile '03 Coupe, bought 2-1/2 years ago with 4000 miles. Figured I'd see 2-3 codes relating to my having pulled fuse #2 to kill the DRLs, and I did see those codes. Unexpectedly, however--on such a babied car--I got 6 or 8 other codes. All were history, except for the 361 and 441 actuator codes. My HVAC works fine, I think; I tried to clear the codes but had limited success because I was in a hurry. I'll try some of the code-clearing suggestions on this very helpful thread next time I have the car out, and report back with results. Hope I don't muck things up worse by messing with it. I wish to Jesus the previous owner had not ordered that worthless "Dual-zone" system.
Drifting
Joined: Jan 2010
Posts: 1,447
Likes: 1
From: Katy TX
After battling B0441 and B0361 HVAC codes off and on for several years 
, I finally decided to do something about it. After searching the helpful CF.com, I stumbled upon a thread where forum member YO-EL responded to someone that was having the same problem that the Actuator simply needed to be reindexed. Since then, I have done some additional research, and have performed and documented reindexing the drivers side HVAC door. I see WAY too many threads here where people are getting these same codes, and other members WRONGLY tell them to add more Freon 
. The above codes have NOTHING at all do to with Freon!
Anyway, long story short, I created a webpage documenting my experience with the codes, how to remove, reindex and reinstall the drivers side actuator and what seemed to cause my codes to popup. For some reason, the drivers side actuator seems to be the one that always acts up. There is probably more to determining how many 'teeth' to index by, or what direction to turn the Actuator drive gear, but from others that have reindexed, 2 teeth counter-clockwise seems to be the way to go. If anybody has more information regarding this, please PM or reply to this thread.
If you need to reindex the passenger actuator, you're on your own.
The process is probably similar, I just can't tell you which way to reindex, and how many teeth.
I thought this might help those who are running into this problem. The usual disclaimers, etc....
Dont' blast me over the page....it's a first draft, and I probably left something out in the removal instructions.
Link
Other great posts in this thread :
http://forums.corvetteforum.com/show...9&postcount=65
http://forums.corvetteforum.com/show...1&postcount=68
EDIT - 12/26/2006 - I would like to just post a little update. So far, my actuator has worked flawlessly since this post was first made. So, I know now for a fact that reindexing is a sure fix. Also, I have received a few PM's over the past few months asking various questions. I would like to state that this project is pretty time consuming. If you page through this thread, you'll see another post where someone did the passenger side actuator by pulling the dash pad. It also looks to be a nightmare. So, if you have a weak stomach for tearing your car apart, please take it to the dealer. This requires someone with patience and small hands to get into tight places. If you can't lay on your back in a ackward position for extended periods of time, you should also pass on tackling this.
Long story short, I really just want to make sure you know what you are getting yourself into if you decide to tackle reindexing/swapping the actuator.
, I finally decided to do something about it. After searching the helpful CF.com, I stumbled upon a thread where forum member YO-EL responded to someone that was having the same problem that the Actuator simply needed to be reindexed. Since then, I have done some additional research, and have performed and documented reindexing the drivers side HVAC door. I see WAY too many threads here where people are getting these same codes, and other members WRONGLY tell them to add more Freon . The above codes have NOTHING at all do to with Freon! Anyway, long story short, I created a webpage documenting my experience with the codes, how to remove, reindex and reinstall the drivers side actuator and what seemed to cause my codes to popup. For some reason, the drivers side actuator seems to be the one that always acts up. There is probably more to determining how many 'teeth' to index by, or what direction to turn the Actuator drive gear, but from others that have reindexed, 2 teeth counter-clockwise seems to be the way to go. If anybody has more information regarding this, please PM or reply to this thread.
If you need to reindex the passenger actuator, you're on your own.
The process is probably similar, I just can't tell you which way to reindex, and how many teeth. I thought this might help those who are running into this problem. The usual disclaimers, etc....
Dont' blast me over the page....it's a first draft, and I probably left something out in the removal instructions.
Link
Other great posts in this thread :
http://forums.corvetteforum.com/show...9&postcount=65
http://forums.corvetteforum.com/show...1&postcount=68
EDIT - 12/26/2006 - I would like to just post a little update. So far, my actuator has worked flawlessly since this post was first made. So, I know now for a fact that reindexing is a sure fix. Also, I have received a few PM's over the past few months asking various questions. I would like to state that this project is pretty time consuming. If you page through this thread, you'll see another post where someone did the passenger side actuator by pulling the dash pad. It also looks to be a nightmare. So, if you have a weak stomach for tearing your car apart, please take it to the dealer. This requires someone with patience and small hands to get into tight places. If you can't lay on your back in a ackward position for extended periods of time, you should also pass on tackling this.
Long story short, I really just want to make sure you know what you are getting yourself into if you decide to tackle reindexing/swapping the actuator.
Melting Slicks
Joined: Sep 2006
Posts: 2,736
Likes: 7
From: Redding CA
Nogee,
Same part number for both sides. I believe the correct factory number is 16163982 which is now 89018365.
I never got a complete answer to my question above, but I know that's the one to use for the automatic control head unit. Maybe the other number I had listed was for a manual control?
However, if you're cost concious, it turns out those specific actuators were used on a number of different GM years, makes and models that had the automatic temperature control. Go to rockauto and look up that part. It should give you a cross reference for which models to go hunting for. I managed to find one in an Oldsmobile. $5 plus tax.
The one I found happened to have a crack in the main gear, but it appears they use the same main gear in just about every one of those actuators, regardless of the model number, even vehicles with manual temperature control. I simply found a good main gear in another model number in a full size truck (they're easier to dig out of the dash) then swapped out the broken main gear for the good one from the truck. I don't remember the exact year of the truck, but I'd guess from the 90's and they all had the same actuator.
If you go that route just be careful not to move the gears around. You'll have to get the main gear back in the same way as the old one. I would think you could get them completely out of "index" if the "blue gear" gets moved compared to that main gear. Maybe snap a photo of the gears before so you can compare it to afterward.....of course that assumes your hub isn't completely broken out of the gear and freewheeling along.
So if all you've got is a broken gear I would think you could just pull it apart and swap in another main gear from just about any GM actuator.
Just a suggestion and hope it might help.
Pete
Same part number for both sides. I believe the correct factory number is 16163982 which is now 89018365.
I never got a complete answer to my question above, but I know that's the one to use for the automatic control head unit. Maybe the other number I had listed was for a manual control?
However, if you're cost concious, it turns out those specific actuators were used on a number of different GM years, makes and models that had the automatic temperature control. Go to rockauto and look up that part. It should give you a cross reference for which models to go hunting for. I managed to find one in an Oldsmobile. $5 plus tax.
The one I found happened to have a crack in the main gear, but it appears they use the same main gear in just about every one of those actuators, regardless of the model number, even vehicles with manual temperature control. I simply found a good main gear in another model number in a full size truck (they're easier to dig out of the dash) then swapped out the broken main gear for the good one from the truck. I don't remember the exact year of the truck, but I'd guess from the 90's and they all had the same actuator.
If you go that route just be careful not to move the gears around. You'll have to get the main gear back in the same way as the old one. I would think you could get them completely out of "index" if the "blue gear" gets moved compared to that main gear. Maybe snap a photo of the gears before so you can compare it to afterward.....of course that assumes your hub isn't completely broken out of the gear and freewheeling along.
So if all you've got is a broken gear I would think you could just pull it apart and swap in another main gear from just about any GM actuator.
Just a suggestion and hope it might help.
Pete
hey bro,
So you have actually tried the oldsmobile actuator in the vette and it works with no issues? or did you just swap the gear?
I'm trying to figure out if that Buick actuator will work cause it's so much cheaper.
Donnie
Melting Slicks
Joined: Sep 2006
Posts: 2,736
Likes: 7
From: Redding CA
Glad to help. This seems to be a common problem. The part also appears to be listed under AC/Delco #15-73044
http://froogle.google.com/froogle?q=...oogle&ct=title
Not exactly sure which model years use the "current service actuator" or the part number, but these can not be re-timed.
Your write up with photos is very detailed. I may be needing it if this problem returns. Thanks for the instructions.
http://froogle.google.com/froogle?q=...oogle&ct=title
Not exactly sure which model years use the "current service actuator" or the part number, but these can not be re-timed.
Your write up with photos is very detailed. I may be needing it if this problem returns. Thanks for the instructions.
Instructor
Joined: Nov 2009
Posts: 109
Likes: 12
From: St. Louis MO
Donnie,
I tried the Olds part from a donor in the bone yard. It had the exact same part number as the one for the vette, so I figured why not. However the Olds one had a cracked main gear. To use it I had to sub in another main gear from a manual unit I got out of a Chevy truck. But it appears to be working just fine up to this point!
I'm not sure what you mean by Buick, but maybe that's the difference between a manual and an automatic that makes the price different?
Hope that helps.
Pete
I tried the Olds part from a donor in the bone yard. It had the exact same part number as the one for the vette, so I figured why not. However the Olds one had a cracked main gear. To use it I had to sub in another main gear from a manual unit I got out of a Chevy truck. But it appears to be working just fine up to this point!
I'm not sure what you mean by Buick, but maybe that's the difference between a manual and an automatic that makes the price different?
Hope that helps.
Pete
Melting Slicks
Joined: Sep 2006
Posts: 2,736
Likes: 7
From: Redding CA
Donnie,
I tried the Olds part from a donor in the bone yard. It had the exact same part number as the one for the vette, so I figured why not. However the Olds one had a cracked main gear. To use it I had to sub in another main gear from a manual unit I got out of a Chevy truck. But it appears to be working just fine up to this point!
I'm not sure what you mean by Buick, but maybe that's the difference between a manual and an automatic that makes the price different?
Hope that helps.
Pete
I tried the Olds part from a donor in the bone yard. It had the exact same part number as the one for the vette, so I figured why not. However the Olds one had a cracked main gear. To use it I had to sub in another main gear from a manual unit I got out of a Chevy truck. But it appears to be working just fine up to this point!
I'm not sure what you mean by Buick, but maybe that's the difference between a manual and an automatic that makes the price different?
Hope that helps.
Pete
Pete,
Thank you so much.
If you look in that post that I quoted you'll see that the part number that was linked to (THE AC delco pn not the GM one)...is different but the actuator itself appears to be the same.
If you pulled one out of an olds and replaced the main gear only but they appeared identical inside and the case bolted up fine?
I mean, you used the case and actuator itself out of the olds and the gear out of a truck..but NONE of the actuator was "corvette" parts and it works fine?
Corvette/(tahoe?)- http://www.google.com/products?q=ac+...971&hl=en&aq=f
Buick- http://www.google.com/products?q=ac+...044&hl=en&aq=f
Instructor
Joined: Nov 2009
Posts: 109
Likes: 12
From: St. Louis MO
Donnie,
Here I answered them one at a time.....
If you look in that post that I quoted you'll see that the part number that was linked to (THE AC delco pn not the GM one)...is different but the actuator itself appears to be the same.
- Almost all of the HVAC actuators GM has look the same from the outside, so you have to be sure you have the correct part number you need for the corvette to start with.
If you pulled one out of an olds and replaced the main gear only but they appeared identical inside and the case bolted up fine?
- Yes the olds one I had and the corvette one were identical inside because they were the exact same GM part numbers. So, then yes, the olds one bolted up fine because again, it was the correct corvette part number. GM has a lot of stuff that has the same part number but is used in different model and year vehicles.
I mean, you used the case and actuator itself out of the olds and the gear out of a truck..but NONE of the actuator was "corvette" parts and it works fine?
- I guess the answer to this one is yes, none of it was "corvette", but since it was the same part number I don't think that really matters.
Long story short, you'll still need the part number that matches the one required for the corvette to start with. My point was that you could swap in a main gear from another model INTO the one that has the corvette part number. That Olds part I started with had the same part number as the one required for the corvette.
Sometimes all folks have wrong with the one they already have is a cracked main gear. So my point was that you didnt' necessarily have to go and get an entirely new "corvette" actuator if that was the only problem. You could just get another similar one and swap out that main gear for one that's not broken. In my case I pulled one, with a different model number, out of a truck and the main gear was identical inside.
Now, if the hub was completely out of the gear and freewheeling in there, I'm not sure if you could easily drop it in and get it back in sync and indexed. But if you've got the time, then I'm sure it's possible. In my case that Olds donor one had a cracked gear, but it wasn't completely busted out.
I hope that helps.
Pete
Here I answered them one at a time.....
If you look in that post that I quoted you'll see that the part number that was linked to (THE AC delco pn not the GM one)...is different but the actuator itself appears to be the same.
- Almost all of the HVAC actuators GM has look the same from the outside, so you have to be sure you have the correct part number you need for the corvette to start with.
If you pulled one out of an olds and replaced the main gear only but they appeared identical inside and the case bolted up fine?
- Yes the olds one I had and the corvette one were identical inside because they were the exact same GM part numbers. So, then yes, the olds one bolted up fine because again, it was the correct corvette part number. GM has a lot of stuff that has the same part number but is used in different model and year vehicles.
I mean, you used the case and actuator itself out of the olds and the gear out of a truck..but NONE of the actuator was "corvette" parts and it works fine?
- I guess the answer to this one is yes, none of it was "corvette", but since it was the same part number I don't think that really matters.
Long story short, you'll still need the part number that matches the one required for the corvette to start with. My point was that you could swap in a main gear from another model INTO the one that has the corvette part number. That Olds part I started with had the same part number as the one required for the corvette.
Sometimes all folks have wrong with the one they already have is a cracked main gear. So my point was that you didnt' necessarily have to go and get an entirely new "corvette" actuator if that was the only problem. You could just get another similar one and swap out that main gear for one that's not broken. In my case I pulled one, with a different model number, out of a truck and the main gear was identical inside.
Now, if the hub was completely out of the gear and freewheeling in there, I'm not sure if you could easily drop it in and get it back in sync and indexed. But if you've got the time, then I'm sure it's possible. In my case that Olds donor one had a cracked gear, but it wasn't completely busted out.
I hope that helps.
Pete
Melting Slicks
Joined: Sep 2006
Posts: 2,736
Likes: 7
From: Redding CA
Pete,
That does help tremendously.
Just so I'm clear...the GM PART NUMBER for the olds and the Vette are the SAME
the AC DELCO NUMBER is different?
Do you know which make/model/year Olds your actuator was off of?
Basically, an actuator off of whatever olds you found...would swap DIRECTLY into a corvette with zero issues?
That does help tremendously.
Just so I'm clear...the GM PART NUMBER for the olds and the Vette are the SAME
the AC DELCO NUMBER is different?
Do you know which make/model/year Olds your actuator was off of?
Basically, an actuator off of whatever olds you found...would swap DIRECTLY into a corvette with zero issues?