How would I Troubleshoot a Blend Door Actuator

2002 KIA SPECTRA
132,000 MILES
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SNETHEJ
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I have a 2002 Kia Spectra and the blend door actuator does not seem to move when I adjust temperature. It appears that it may have been that way for awhile (just bought the car) because the metal linkage between the actuator and the blend door piece seems to have been disconnected at sometime. It looks like the big white plastic piece on the blend door would have had to have been removed and then replaced to get the linkage disconnected.

What would be the best approach in diagnosing what may be the issue as to why the actuator does not move?

The electrical connection on the actuator seems to be a blue plug with maybe six contacts in it (I didn't remove that yet, since I wouldn't know what to look for with it).

I also do not have issues with hot/cold air if I move the blend door manually.

Thanks.
May 29, 2012 at 1:50 PM
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WRENCHTECH
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Hello,

It sounds like you have a bad connection but to be sure here is a guide to elp and the HVAC wiring diagrams so you can see how the system works.

https://www.2carpros.com/articles/how-to-check-wiring

Check out the diagrams (Below). Please let us know what you find. We are interested to see what it is.
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May 29, 2012 at 3:38 PM
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KHLOW2008
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The rod from the actuator near the throttle pedal is easily and often disconnected from being bumped by the drivers foot.

Reinstalling it usually works.
May 29, 2012 at 6:56 PM
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KHLOW2008
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This shows why we are one of the best car repair sites around, our commitment to our work and would always try our best to provide the best answer.

Have a great day.
May 29, 2012 at 7:11 PM
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SNETHEJ
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Here's a pic of the passenger side where the actuator (at least what I think it is, with the bigger red circle) and the the blend door (controlled by the big white plastic piece) are located. The smaller red circle is where it looks like the linkage should connect the two is.

The arm did not move at all when I adjusted the temperature, and I tried to gently move it manually without success. I have not removed it, yet.
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May 29, 2012 at 7:32 PM
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WRENCHTECH
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Yep, those rods appear disconnected.
May 29, 2012 at 7:44 PM
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SNETHEJ
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Here's a better pic with description of my question (I hope).
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May 29, 2012 at 7:46 PM
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WRENCHTECH
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It appears that other rod goes to a piece of linkage above the white disc.
May 29, 2012 at 7:54 PM
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SNETHEJ
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But should the actuator move when the temperature control is changed from hot to cold (the note in the picture, "This does not move")? In the picture, the thermostat is set to cold, and the blend door piece is rotated to get cold, but the actuator is showing and stuck where it would be if the thermostat is set to hot.
May 29, 2012 at 8:12 PM
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SNETHEJ
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Back to the original question, "... diagnosing what may be the issue as to why the actuator does not move," Wrenchtech originally posted:

"Does the actuator even shows any hints of trying to move when adjusted? Try this with the actuator removed and plugged in."

My answer is that is does not move currently, but I'm not sure what you are getting at when you want me to do. With the established lack of linkage, would that be considered removed and plugged in, indicating that the actuator is not moving at all? Or do I need to actually unscrew it and remove the unit for what you were asking?
May 30, 2012 at 10:57 AM
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KHLOW2008
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Unplug the wire connector is what he meant. With wires unplugged, manually try to move the actuator lever to another position before plugging wire back.

I don't have any more detailed diagram of the actuator but from the picture, there seems a slot further inwards to the words you have written "What is this linkage for" If I am not misteken that linkage should be slotted into it.

Seems that linkage is not dislodged but intentionally left unattached or the person who removed the actuator previously does not know how to reinstall it.

If you remove the screw holding the white plae and remove the plate, you should be ble to understand how it should go in.

May 30, 2012 at 12:26 PM
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SNETHEJ
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I disconnected the blue connector (in my pics above) and tried to force the black arm (with the linkage still disconnected), and it would not move. I put enough pressure on it going either way that I felt that adding more would risk breaking it.
May 30, 2012 at 5:48 PM
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WRENCHTECH
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You're not going to move that arm. It's connected to the gears in the motor. That requires power. He was referring to the lever for the door itself.
May 30, 2012 at 8:15 PM
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SNETHEJ
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Going back to pictures, the attached picture is how I interpreted the statement:

KHLow2008: "Unplug the wire connector is what he meant. With wires unplugged, manually try to move the actuator lever to another position before plugging wire back."

The door itself has not been in question with me. It moves. I once had hot air, now I have cold. It would be nice to control it from the thermostat.

Is the actuator bad (mechanical problem with actuator), or is there an electrical problem going up to the actuator? How can I determine which (I have no electrical diagrams or spare actuators)?
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May 30, 2012 at 8:37 PM
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WRENCHTECH
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If you're going to attempt to apply power anywhere here, make damn sure the control head is not connected to it at that time. This is a reverse polarity motor so you could be sending power back through a grounding transistor and fry the whole thing.
May 30, 2012 at 8:46 PM
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BALLON JEANS
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Thank u KHLow2008 you r right problem solved
Dec 19, 2012 at 7:51 AM
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KHLOW2008
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You're welcome.
Dec 19, 2012 at 10:07 AM
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MARK 186
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What part of the dashboard do I take out on the passenger side to get to the blen door actuator to change actuator the ac dose not come out of the front vents
Mar 5, 2019 at 12:37 PM (Merged)
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KHLOW2008
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Not very sure but removing the glove box should give you a lot of space to work on.
Mar 5, 2019 at 12:37 PM (Merged)