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Blend Door Actuator Issue Thread

Who has had blend door actuator problems?

  • '14 Fiesta ST

    Votes: 143 28.9%
  • '15 Fiesta ST

    Votes: 144 29.1%
  • '16 Fiesta ST

    Votes: 143 28.9%
  • '17 Fiesta ST

    Votes: 65 13.1%

  • Total voters
    495

maestromaestro

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Any particular video of the procedure that you recommend? I’ve seen several posted ITT, but I’d like the 20 minute route please.
There's one on YT. The route is NOT to take the knee airbag off, but to take the trim around the steering wheel off to gain access. You'll need a stubby socket driver - or, if you're lucky, you could unscrew the fasteners with just the torx bit in your hand.

Sent from my Pixel 3 XL using Tapatalk
 


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It was a cold Thursday evening, I waited and waited for my girlfriend to get into my car as usual to head back to my apartment. I am prepared. I read about it. I watched many videos about it. I planned in my head all the steps I needed to do over and over again. I can do this, the best way to do it. I won't screw up. It will take 30min but will last for a long time. But for the past year and a half, nothing happened. But I can't complaint for all the good time we have. This evening, my girlfriend decided to stop by to pick up a bottle tequila instead of the usual merlot on the way back. Then, it finally happen. I depress the Start button, engine roaring, then..."clack...clack...clack.." "clack...clack...clack.." Yep, the blend door actuator on my 2017 fiesta st finally has malfunctioned.
 


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My guess is they predominantly fail in the cold. Cold brittle plastic and a stiff moving blend door.
Easy fix, but frustrating to have to pay for a bad design. Ford should subsidize the part, sell them for $5.
 


Intuit

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========================== PROLONGING THE LIFE OF YOUR BLEND DOOR ACTUATOR ==========================

A prior car with manually actuated blend doors taught me what stresses them.

TIPS & INFO....

Blend doors are moved back into a default position several minutes after every ignition off.

Manually operating the blend doors required increased force when the blower motor was set for max speed.
* Turn the blower down prior to ignition off.

Frigid temperatures stress them.
* Turn the blower down to low prior to ignition off.
* When first start the car, give it a dozen seconds or so before activating max defrost. As you're hitting that max defrost button, *immediately* turn down the blower motor speed. After it sssllllloowwllyy moves the doors into position (you can hear/feel the airflow changing,) put the blower motor speed back to max.

Manually operating the blend doors required a lot of force, almost to the point of breaking the levers behind the dash when attempt to operate them with high negative cabin pressures. (highway speeds with windows cracked open or open)
* When at highway speeds, temporarily close all windows (including sunroof) prior to changing your vent and temperature settings.
* Turn blower speeds down to 50% or below before changing vent settings.

Blend doors are constantly receiving minor adjustments when the HVAC is set on anything other than Hi/Lo.
* If you can stand it, keeping the setting on either "Hi" or "Lo" will eliminate the constant adjusting that goes on.



Following the above guidelines, should either greatly extend the life of, or eliminate the failure of this mechanism.
 


maestromaestro

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========================== PROLONGING THE LIFE OF YOUR BLEND DOOR ACTUATOR ==========================

A prior car with manually actuated blend doors taught me what stresses them.

TIPS & INFO....

Blend doors are moved back into a default position several minutes after every ignition off.

Manually operating the blend doors required increased force when the blower motor was set for max speed.
* Turn the blower down prior to ignition off.

Frigid temperatures stress them.
* Turn the blower down to low prior to ignition off.
* When first start the car, give it a dozen seconds or so before activating max defrost. As you're hitting that max defrost button, *immediately* turn down the blower motor speed. After it sssllllloowwllyy moves the doors into position (you can hear/feel the airflow changing,) put the blower motor speed back to max.

Manually operating the blend doors required a lot of force, almost to the point of breaking the levers behind the dash when attempt to operate them with high negative cabin pressures. (highway speeds with windows cracked open or open)
* When at highway speeds, temporarily close all windows (including sunroof) prior to changing your vent and temperature settings.
* Turn blower speeds down to 50% or below before changing vent settings.

Blend doors are constantly receiving minor adjustments when the HVAC is set on anything other than Hi/Lo.
* If you can stand it, keeping the setting on either "Hi" or "Lo" will eliminate the constant adjusting that goes on.



Following the above guidelines, should either greatly extend the life of, or eliminate the failure of this mechanism.
Interesting thought. Much like the people who won't adjust their lifestyle even when they know that going to Chipotle is threatening to their lives, I would rather spend $12 every couple of years rather than be anal about the temperature settings. But that's me.
 


Intuit

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Interesting thought. Much like the people who won't adjust their lifestyle even when they know that going to Chipotle is threatening to their lives, I would rather spend $12 every couple of years rather than be anal about the temperature settings. But that's me.
The two most important points are:

Manually operating the blend doors required a lot of force, almost to the point of breaking the levers behind the dash when attempt to operate them with high negative cabin pressures. (highway speeds with windows cracked open or open)
  • When at highway speeds, temporarily close all windows (including sunroof) prior to changing your vent and temperature settings.
  • Turn blower speeds down to 50% or below before changing vent settings.

Frigid temperatures stress them.
  • Turn the blower down to low prior to ignition off.
  • When first start the car, give it a dozen seconds or so before activating max defrost. As you're hitting that max defrost button, *immediately* turn down the blower motor speed. After it sssllllloowwllyy moves the doors into position (you can hear/feel the airflow changing,) put the blower motor speed back to max.

When I say "Frigid", I'm talking roughly 12 and below temps.

I think that's really all you have to do. Personally I spend most of my time on a motorcycle and love heat so it spends most of the year on "hi" and simply adjust blower speeds. If there's no ice I crack open the sunroof during the Winter once the output gets good hot.
 


maestromaestro

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Mine has failed twice in Houston weather. So, no frigidity here. The only strain is when in the heat, the AC starts to blast WOT when I first start the car. You ‘may’ extend the life of the actuator, but given that it is a quick and cheap fix, imho, no need to obsess.

But, of course, points taken. Ford should have made these more robust.
 


M-Sport fan

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My guess is they predominantly fail in the cold. Cold brittle plastic and a stiff moving blend door.
Easy fix, but frustrating to have to pay for a bad design. Ford should subsidize the part, sell them for $5.
...or at least fully re-design/re-engineer the materials used in the replacement doors/gears to enable them to last more than a few years at most. ;) :(
 


Intuit

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...or at least fully re-design/re-engineer the materials used in the replacement doors/gears to enable them to last more than a few years at most. ;) :(
Anyone ever attempt to cross-reference the two actuators with a Mercury or Lincoln vehicle? (IIRC Mercury has been long defunct I think so never mind them.)
 




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