Blend Door Actuator

[Frost]

I've installed this thing twice now, and for some reason I can't manage to get the actuator lined up right....it keeps slipping off the gears and getting stuck with air only coming out of the defrost vents. I live in South Texas and it's May. Defrost vents aint cutting it.

 

Questions:

 

-When lining up the teeth on the white gear with the teeth on the actuator blade, what is the correct start position for the gears to ensure full movement and use of all levels of vents?

 

-Does it help to have the vehicle running while you do this? If so, what mode should I have my climate control on?

 

-Do I plug in the actuator cable before lining up the gears or after?

 

I'd really appreciate it if one of yall that have done this could walk me thru....it seems like such a simple problem but apparently I'm not getting it....

 

Thanks.

[bill190]

Following the instructions in the GM factory service manual for my 92 (may not apply to your vehicle but makes basic common sense to me)...

 

It says to remove the old actuator, then BEFORE installing the new actuator, connect the new actuator to the wires, then start the car. Then turn on the A/C and let the replacement actuator position itself to where it should be (and where the door would have been left upon removing the old actuator).

 

Then the new actuator is now positioned where the old actuator had the door before removal.

 

So now install the new actuator and the door will be where the actuator thinks it is.

 

If you did not follow the factory installation instructions and just installed the new actuator, then the actuator may think it is in one position and the door may actually be in another position!

 

So you would need to resynchronize the motor position with the door position. The book does not say anything about resolving this (probably because this situation should not happen?)

 

And I suppose if it was installed without synchronizing the motor and door, then the motor could have gone to one extreme or another (past where the door could physically move) and then damage to the motor or gears may have occurred??? I don't know...

 

To say this another way...

 

The actuator and door might have positions...

 

Actuator: 1, 2, 3.

Door: 1, 2, 3.

 

When you remove the old actuator, say the old actuator is at 2 and the door is also at 2. (Synchronized)

 

Then you go buy a new actuator and say it comes in position 1. You would need to get it to go to position 2 PRIOR to installing it. So you would do this by connecting the electrical connector to the actuator PRIOR to installing it, and turning on the vehicle. Then this would move the actuator to position 2.

 

Then the new actuator and door would be in the same positions when you installed the new actuator.

 

And you would of course not want to change the positions of the A/C controls while you had any actuator removed.

[ss502gmc]

I have a similar problem on my 01 silverado. the actuator was replaced by the shop i bought the truck from and it stopped working again and is now out of warranty. Is this a hard part to access? They made it seem like it was a space shuttle launch to replace it but i was wondering if its something i could tackle my self and if i could get some pointers on how to replace. Any input would be great!! Thanx

[Frost]

That's exactly what I was looking for, thanks. My problem is, I pulled the old actuator out and didn't pay any attention to what position it was in. And I didn't have the truck on to start it at the correct position. I'm going to remove and plug in unmounted w/ the vehicle running, hopefully I haven't stripped the gears.

 

Thanks Again.

 

Following the instructions in the GM factory service manual for my 92 (may not apply to your vehicle but makes basic common sense to me)...

 

It says to remove the old actuator, then BEFORE installing the new actuator, connect the new actuator to the wires, then start the car. Then turn on the A/C and let the replacement actuator position itself to where it should be (and where the door would have been left upon removing the old actuator).

 

Then the new actuator is now positioned where the old actuator had the door before removal.

 

So now install the new actuator and the door will be where the actuator thinks it is.

 

If you did not follow the factory installation instructions and just installed the new actuator, then the actuator may think it is in one position and the door may actually be in another position!

 

So you would need to resynchronize the motor position with the door position. The book does not say anything about resolving this (probably because this situation should not happen?)

 

And I suppose if it was installed without synchronizing the motor and door, then the motor could have gone to one extreme or another (past where the door could physically move) and then damage to the motor or gears may have occurred??? I don't know...

 

To say this another way...

 

The actuator and door might have positions...

 

Actuator: 1, 2, 3.

Door: 1, 2, 3.

 

When you remove the old actuator, say the old actuator is at 2 and the door is also at 2. (Synchronized)

 

Then you go buy a new actuator and say it comes in position 1. You would need to get it to go to position 2 PRIOR to installing it. So you would do this by connecting the electrical connector to the actuator PRIOR to installing it, and turning on the vehicle. Then this would move the actuator to position 2.

 

Then the new actuator and door would be in the same positions when you installed the new actuator.

 

And you would of course not want to change the positions of the A/C controls while you had any actuator removed.

[bill190]

I have a similar problem on my 01 silverado. the actuator was replaced by the shop i bought the truck from and it stopped working again and is now out of warranty. Is this a hard part to access? They made it seem like it was a space shuttle launch to replace it but i was wondering if its something i could tackle my self and if i could get some pointers on how to replace. Any input would be great!! Thanx

 

Well if you have the right instructions (GM factory service manual set for your specific vehicle/year), and you follow those directions, then you are much more likely to be successful with your repairs.

 

Also in the front of each section in these books, it explains how the various components work. What makes them tick! And if you understand how something SHOULD work, then you will know when it is not working.

 

The best part about having the proper instructions to do this work is these books will show diagrams of WHERE various things are located. I use this feature all the time. Where is that silly thing???? Then I look in the book and with a little hunting around, I can find what I am looking for.

 

Also with a factory book you can read about what steps are necessary to replace a part.

 

It may start out by saying to remove the steering column and the entire dash board! Then you might decide that is too much for you and then have a dealer do the repair for you instead.

 

Or it may say to remove the glove compartment, then the part is right there. In this case it would appear to be easy, so then you might do it yourself.

 

The way I look at it, these books are a tool just as important as a socket set or other tools you would use to repair something. But ESPECIALLY with electrical/electronic things. In some cases, if you don't follow directions, nasty things can happen!

[bill190]

That's exactly what I was looking for, thanks. My problem is, I pulled the old actuator out and didn't pay any attention to what position it was in. And I didn't have the truck on to start it at the correct position. I'm going to remove and plug in unmounted w/ the vehicle running, hopefully I haven't stripped the gears.

 

But have things changed now?

 

Figure out where the door actually is now (maybe the new actuator installed moved it from where it was?)

 

Maybe you will need to manually move it to a certain position?

 

Then the A/C controls would need to be set to that same position and then you could connect the new actuator and turn on the vehicle, then this would move the actuator motor to that same position.

 

Then just prior to installing the actuator (this time), you would have 3 things all in the same position. The door, the A/C controls, and the new actuator.

[Frost]

That's exactly what I was looking for, thanks. My problem is, I pulled the old actuator out and didn't pay any attention to what position it was in. And I didn't have the truck on to start it at the correct position. I'm going to remove and plug in unmounted w/ the vehicle running, hopefully I haven't stripped the gears.

 

But have things changed now?

 

Figure out where the door actually is now (maybe the new actuator installed moved it from where it was?)

 

Maybe you will need to manually move it to a certain position?

 

Then the A/C controls would need to be set to that same position and then you could connect the new actuator and turn on the vehicle, then this would move the actuator motor to that same position.

 

Then just prior to installing the actuator (this time), you would have 3 things all in the same position. The door, the A/C controls, and the new actuator.

 

 

Does your book say anything about what the 3 notches on the actuator indicate? There's a left, mid, and right dash mark at about 10,12,and 2 o'clock on the actuator but no explanation. I need to get my hands on one of the factory svc books, my Haynes manual is worthless on this particular problem.

[bill190]

...Does your book say anything about what the 3 notches on the actuator indicate? There's a left, mid, and right dash mark at about 10,12,and 2 o'clock on the actuator but no explanation. I need to get my hands on one of the factory svc books, my Haynes manual is worthless on this particular problem.

 

I don't see anything in my book about this, but my books are for a 92.

 

I don't think getting a factory repair manual would help much more than what I have said above. These tend to give procedures for replacing things, but don't go into much detail about markings or notches on things.

 

So I think at this point you would need to figure this out on your own. I would guess that the markings might indicate where the door should be for various A/C settings?

 

Is there 3 different positions the door could be in perhaps? (I don't know)

 

Maybe defrost, air vents, and floor?

 

Can you take a picture and post it of what you are connecting the actuator to? And of the actuator?

 

Can you make the door move by moving the door or gear with your hand or a tool?

 

Can you tell where the door is by looking or by where the air is coming out?

 

I would think the goal here would be to get the door into a known position, then get the actuator and A/C switches into that same position, then install the actuator.

 

How you do that might take a bit of ingenuity...

[bill190]

I was just thinking about this and came up with an idea which might help...

 

First of all, I suppose I should get the right door in mind! I kept thinking the door in question controls the air flow to the vents, but actually this door controls the temperature correct? Hot cold?

 

Anyway if you can connect the new actuator to the wire, then fiddle with the A/C controls. Set it to all the way cold and watch the actuator. Then set it to all the way hot and watch the actuator. Maybe mark the gear with a black pen (if white gear) and you can see where it moves.

 

Then try moving the door yourself to either extreme (with the actuator out). Notice how this works.

 

Then move the actuator to one extreme or the other, and move the door into the same position. Then install the actuator. Make sense? (Or if this is for another door/function, use the A/C controls to do likewise.)

[redvett]

Try this.

 

When replacing the HV AC control module it will be necessary to allow the HV AC control module to perform a re-calibration process.

IMPORTANT: Do not adjust any controls on the HVAC control module while the HVAC control module is calibrating. If interrupted improper HVAC

performance will result.

Place the ignition switch to the OFF position.

Disconnect the scan tool.

Install the HVAC control module.

Re-connect all previously disconnected components.

Start the vehicle.

Wait 40 seconds for the HVAC control module to re-calibrate.

Verify that no DICs have set as current DICs.

When replacing the motor assembly it will be necessary to allow the HV AC control module to perform a re-calibration process. When installing the

motor assembly be sure to perform one of the following:

IMPORTANT: Do not adjust any controls on the HVAC control module while the HVAC control module is calibrating. If interrupted improper HVAC

perfonnance will result.

Preferred Method (\VI Scan Tool)

Clear all DICs

Place the ignition switch in the OFF position.

Install the motor assembly.

Re-connect all previously disconnected components.

Start the vehicle.

With the scan tool. initiate the Motor Re-calibration feature of the HV AC module Special Functions menu.

Verify that no DICs have set as current DICs.

IMPORTANT: Do not adjust any controls on the HVAC control module while the HVAC control module is calibrating. If interrupted improper

HV AC performance will result

Alternate Method (\VIO Scan Tool)

Clear all DICs

Place the ignition switch to the OFF position.

Disconnect the scan tool.

Install the motor assembly.

Re-connect all previously disconnected components.

Remove the HV ACIECAS fuse for a minimum of 10 seconds.

Re-install the HVACIECAS fuse.

Start the vehicle.

Wait 40 seconds for the HVAC control module to re-calibrate.

Verify that no DICs have set as current DICs.