Cannot change air from floor to vent or defrost why?

Tiny
TOM T-GUNZ RATH
  • MEMBER
  • 2004 BUICK LESABRE
  • 3.7L
  • 6 CYL
  • 2WD
  • AUTOMATIC
  • 102,000 MILES
No matter which selection I make air only blows from floor vents. It will not blow through defrost or front vents. This is manual temperature control set up. Blend door actuator works (can change temperature). Please help, this is my wife's car and she is panicking because defrost won't work. Thanks in advance.
Friday, March 6th, 2020 AT 3:03 PM

44 Replies

Tiny
JACOBANDNICKOLAS
  • MECHANIC
  • 109,747 POSTS
Hi,

It sounds like the mode door actuator has failed. The mode door is what changes air flow directions. I would remove it and check to see if it is operating when you change directions. If not, replace it. Here is a guide to help you step by step with instructions in the diagrams below to show you how on your car.

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

Here are the directions specific for your vehicle as far as replacement. The attached pictures correlate with the directions.

MODE ACTUATOR REPLACEMENT

REMOVAL PROCEDURE
1. Remove the left sound insulator.
2. Remove the knee bolster.
3. Remove the IPM.
4. Disconnect the electrical connector from the mode actuator.

5. Remove the mode actuator retaining screws (1).
6. Remove the mode actuator.

INSTALLATION PROCEDURE

1. Align the mode door levers with the cam slots.
2. Install the mode actuator.
3. Install the mode actuator retaining screws (1).

NOTE: Refer to Fastener Notice in Service Precautions.

Tighten
Tighten the screws to 1.4 N.m (12 lb in).

4. Connect the electrical connector to the mode actuator.
5. Install the IPM.
6. Install the knee bolster.
7. Install the left side sound insulator.
8. Recalibrate the actuator.

If you look at the last pic, it shows location.

Check out the diagrams (Below). Let us know what happens and please upload pictures or videos of the problem.

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Friday, March 6th, 2020 AT 9:13 PM
Tiny
TOM T-GUNZ RATH
  • MEMBER
  • 3 POSTS
Thank you Joe. That is exactly what it was. Removed the actuator, started the car, turned on the air, manually moved the doors to make sure air changed between vent, defrost and floor and it did. Now just need to install the new actuator. Thank you so much. You saved me approximately $300.00.
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Sunday, March 8th, 2020 AT 4:03 AM
Tiny
TOM T-GUNZ RATH
  • MEMBER
  • 3 POSTS
Oh, not to mention my wife's and my peace of mind.
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Sunday, March 8th, 2020 AT 4:10 AM
Tiny
JACOBANDNICKOLAS
  • MECHANIC
  • 109,747 POSTS
You are very welcome. I'm glad you figured it out.

Take care and feel free to come back anytime. Also, if you need help or run into trouble when reinstalling it, let me know.

Joe
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Sunday, March 8th, 2020 AT 7:54 PM
Tiny
DHABICHT1
  • MEMBER
  • 1 POST
  • 2002 BUICK LESABRE
  • 6 CYL
  • 2WD
  • AUTOMATIC
  • 67,000 MILES
I'm sure there is a mode actuator somewhere like the blend door but I don't see it. Has electronic climate control with passenger controls
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Monday, March 22nd, 2021 AT 2:21 PM (Merged)
Tiny
ASEMASTER6371
  • MECHANIC
  • 52,797 POSTS
Good evening,

Good chance the mode door actuator is the issue. I attached a picture and the procedure for you to view.

Roy

1. Remove the left sound insulator.
2. Remove the knee bolster.
3. Remove the IPM.
4. Disconnect the electrical connector from the mode actuator.
5. Remove the mode actuator retaining screws (1).
6. Remove the mode actuator.
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Monday, March 22nd, 2021 AT 2:21 PM (Merged)
Tiny
ED MCK
  • MEMBER
  • 3 POSTS
  • 2000 BUICK LESABRE
  • 3.8L
  • 6 CYL
  • 2WD
  • AUTOMATIC
  • 210,000 MILES
After removing the glove box I've found the actuator is laying there. It's not blowing out the dash vents now. The air blew fine yesterday. A few years ago I bypassed the heater core to just have A/C in Florida. I think the actuator under the dash behind the glove box isn't the problem? Maybe under the dashboard the actuator isn't controlling the air out the dash vents?
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Monday, March 22nd, 2021 AT 2:21 PM (Merged)
Tiny
ASEMASTER6371
  • MECHANIC
  • 52,797 POSTS
Good afternoon,

Most likely the mode door actuator has failed. It is under the dash and easy to access.

I attached the procedure and a picture for you to view.

Roy

1. Remove the left sound insulator.
3. Remove the electrical connector from the mode actuator.
4. Remove the mode actuator retaining screws (1).
5. Remove the mode actuator.

INSTALLATION PROCEDURE

imageOpen In New TabZoom/Print

1. Align the mode valve levers with the cam slots.
2. Install the mode actuator.

NOTE: Refer to Fastener Notice in Service Precautions.

3. Install the mode actuator retaining screws (1).

Tighten
Tighten the fasteners to 1.4 N.M (12 lb in).

4. Connect the electrical connector to the mode actuator.
5. Install the knee bolster.
6. Install the left side sound insulator.
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Monday, March 22nd, 2021 AT 2:21 PM (Merged)
Tiny
ED MCK
  • MEMBER
  • 3 POSTS
Just wondering if this was on the driver's side or the passenger side. The diagram is exploded I see. Thank you, Eddie
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Monday, March 22nd, 2021 AT 2:21 PM (Merged)
Tiny
ASEMASTER6371
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It is on the drivers or left side as stated in the procedure.

Roy
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Monday, March 22nd, 2021 AT 2:21 PM (Merged)
Tiny
ED MCK
  • MEMBER
  • 3 POSTS
That's great as it says left but one I looked at was behind the glovebox on the left so I got confused. Thanks, Eddie
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Monday, March 22nd, 2021 AT 2:21 PM (Merged)
Tiny
ASEMASTER6371
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You are welcome.

Always glad to help.

Roy
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Monday, March 22nd, 2021 AT 2:21 PM (Merged)
Tiny
PATRICK CALLAGHAN JR.
  • MEMBER
  • 9 POSTS
  • 2000 BUICK LESABRE
  • 3.8L
  • V6
  • 2WD
  • AUTOMATIC
  • 132,500 MILES
The mode door actuator is not working. I know it has to come out but I cannot figure how to access it. I can only get my finger tips in there. It is number 2 in the diagram. The actuator seems blocked by the dash structure.
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Monday, March 22nd, 2021 AT 2:21 PM (Merged)
Tiny
ASEMASTER6371
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Good afternoon,

Are you accessing it from the bottom?

I attached the procedure and a picture for you.

Roy

REMOVAL PROCEDURE

imageOpen In New TabZoom/Print

1. Remove the left sound insulator.
3. Remove the electrical connector from the mode actuator.
4. Remove the mode actuator retaining screws (1).
5. Remove the mode actuator.
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Monday, March 22nd, 2021 AT 2:21 PM (Merged)
Tiny
PATRICK CALLAGHAN JR.
  • MEMBER
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After step #1 there is not enough room to reach up to get to the screws. Like I said, the dash structure is blocking access.
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Monday, March 22nd, 2021 AT 2:21 PM (Merged)
Tiny
ASEMASTER6371
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Are you sure you are on the correct actuator?

Is this auto climate control?

Roy
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Monday, March 22nd, 2021 AT 2:21 PM (Merged)
Tiny
PATRICK CALLAGHAN JR.
  • MEMBER
  • 9 POSTS
Yes, it is the CJ2 dual zone climate control. It is #2 in my attached picture.
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Monday, March 22nd, 2021 AT 2:21 PM (Merged)
Tiny
ASEMASTER6371
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Okay, that's the issue.

For the auto climate control, the actuator is at the top of the housing where you cannot access it without removing the dash cluster. It has to be moved forward to get to the actuator.

Is this something you will be doing yourself?

Roy
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Monday, March 22nd, 2021 AT 2:21 PM (Merged)
Tiny
PATRICK CALLAGHAN JR.
  • MEMBER
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It is on the side per my attached drawing. I got it out and bench tested it and it worked. So now back to square one.
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Monday, March 22nd, 2021 AT 2:21 PM (Merged)
Tiny
ASEMASTER6371
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What drawing?

Roy
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Monday, March 22nd, 2021 AT 2:21 PM (Merged)

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