Blend door actuator does not respond?

I would agree a junkyard part is of unknown quality and I try to diagnose and verify a problem and not take the route of throwing parts at it but I have been unsuccessful at identifying the issue, other mechanics I have contacted are unable to identify the problem, and if I were to purchase new parts I doubt a $500.00 bill would cover the parts alone not to mention flashing the unit, the auto part stores I have checked don't have a listing for the HVAC module making it a dealer part, and I would not be able to return parts if they did not correct the problem.
Being the junkyard parts are acting exactly the same as the modules that were in the car I think it is highly unlikely I would have found modules with the exact same issues. Short of purchasing new modules I suppose I could reaffirm the modules were not the issue, by returning to the junkyard and trying modules from different vehicles if they also make no difference I would be confident the modules were not the issue.
The pictures below are of the modules I had replaced the originals are now back in place. I have also included a component locator diagram from my shop manual it's a little different than the one you sent, the view is looking at the location of the IPM module from the viewpoint of the firewall under dash in area of glove box.
Since I have already looked up the necessary information and to minimize the time you invest in doing the same I have included connector end views of the pins or cavities I have listed in the text that I have used to obtain values with my VOM, wiring diagrams, data values for actuators, and system operation overview.
One last thing my shop manual was somewhat confusing in describing the fuse to remove for a minimum of one minute, I had referred back to (wiring diagram 1) being the CSTR/SBM fuse was hot at all times, I felt this was the fuse referred to but I also pulled the HVAC fuse to be sure I had the correct fuse and instruction covered.
I'm not always on the computer but I will check and if you require additional information I will get back to you as soon as can. Thank you

Roy, the thing that I don't get is the actuator will go stop to stop through its initial self test at the beginning of each ignition cycle but will not when commanded from the HVAC module on the dash. To me this would indicate the problem is not the actuator motor and the shop manual doesn't indicate if the self test is initiated from the HVAC module or the IPM module. One mechanic I spoke with asked if I ran onboard diagnostics I searched online and I only found a detailed description stating to enter the diagnostic mode for a 1991 Park Ave by pressing both the off and warm buttons on the HVAC module for 5 seconds but mine did not enter into the diagnostic mode. I looked in my shop manual to see if there was a procedure for my 2002 Park Ave but I did not find one. Ron

No, I do not I only have a code reader. When contacting a local repair shop I asked if scanning the vehicle would help in diagnosing the problem and they said it would not.

Hello Roy I posted a question in regards to an inoperative blend door actuator which you responded to I couldn't find your URL or I would have gotten back to you sooner.
The reason I contacted you originally was because after checking and rechecking my wiring and replacing the original blend door actuator it still was in operative.

After having tried two new actuators and trying a different HVAC module and the module under the glove box and still not making the repair I thought I would try the actuators from vehicles in a local salvage yard. I single handedly emptied every car there and had mixed results of faulty actuators to some that move somewhat. I had stopped in a local auto parts store and talked to one of the counter people and asked him is it possible I could have two new actuators that were bad, he smiled at me and said he went through three before installing a fourth which worked. Since the cold weather was coming and I needed to have it working I ordered a third actuator this time from Rock Auto,

STANDARD MOTOR PRODUCTS F04009 #16164972, 89018375 TechSmart Info
Left; w/ Dual Zone Temp Control; Front
Part image $89.79

Which had a three-year warranty, voila it worked ! Apparently there seems to be a quality control and also a dependability issue with these parts, what made this so frustrating is that my wiring checked out but the new units still did not work. Being you offered to help me I thought you would appreciate knowing as well as your readers in the event someone else ran into the same issue that you may offer them this insight and may prevent a lot of frustration and wasted time looking for a defect that doesn't exist.

Again I would like to thank you for your time and offer to help me. Ron

Warm air on driver side air. Removed actuator and plugged back in to determine if full range movement as I select temperature change. Actuator moves full range. I attempted to manually turn blend door. It moves slightly. Will not turn full range. Can the blend door be accessed to check for obstruction?

Lacking in detail.

The driver side of my car does not heat only cools while the passager side does both. I am trying to replace the blend door actuator but can only find the passengers side one.

I have three plastic pieces that goes before you put the panel mode actuator on. Don't know what order they go in.

Heat blend actuator door, where is it on a 1998 buick park avenue ultra?

There are three that I'm aware of. Two left side under dash. One for driver side blend door and the other controls defrost/vent/floor position door. This one is very difficult maybe impossible to remove and check without removing entire dash. You can manipulate it by moving the linkages with your finger. It has a semi-circular lever that the actuator causes to pivot around to move the blend doors. I had to manually move mine to the defrost position for winter weather. I going to replace the programmer before I attempt to remove the entire dash. The programmer is inexpensive and can be googled online if you dont want to pay dealer.

Here is a guide to help you see what you are in for when doing the job.

https://www.2carpros.com/articles/replace-blend-door-motor

Check out the diagrams (Below). Please let us know if you need anything else to get the problem fixed.

Cheers

How would I get to the linkages because I think some debris is causing it to get stuck open or something. It blows hot air on the drivers side but cold air on the passenger side. Could I manipulate it to stay "open"?

Probably not debris. Could be the heater programmer or control module in dash. Control module has four resistors that overheat in circuit board and cause solder joints to loosen and malfunction.

To answer your question there is an actuator on the passenger side as well. There are three small 11/32 bolts fastening the actuator. You can remove the actuator (See picture) and move the blend door rod (end of white rod under actuator counterclockwise with your fingers. Down fully counterclockwise is heat mode.