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Hello-
I am not getting hot air out of defrost vents. Previously, turning the selector to defrost would result in an audible "pop" as what seemed to be a door closing in a duct under the dash followed by a rush of air movement out of the defrost vents. Now there is no "pop" and no air out of the vents. Suggestions? Not sure if I am dealing with a vacuum leak here, or a bad actuator box in the dash. Thanks in advance for shared experiences that have resolved this. Note: Hubs are manual, not vacuum.
Update: I can confirm that the arm behind the glove box appears to be moving as expected when the selector is moved from heater to defrost to vents etc. However still no air out of defrost and no "pop" when defrost is selected.
In addition, replacing the actuator box behind the glove box (PN F81H-19E694-AD) has no effect. The output arm associated with the actuator box can be observed turning when the hot-cold **** on the dash is turned.
Let's see, the fresh air vent is under the dash down by passenger floor board. Then next in line is the blend door. It is kinda left edge of the glovebox and electrically controlled. Then you've got the diverter with 2 separate vacuum control doors to break it out for floor, vent, defrost, or a mix. Oh yeah there's also a vacuum splitter tucked up in the passenger floor board area about smack in the middle of the glovebox.
Hello Udsuth78-
Thanks for your observations.Yes, air is coming out of all vents except defrost vents. Actuator directly behind glove box appears to be functioning normally.
Have you swapped actuators other than the one behind the glove box?
Hello Udsuth78-
Thanks for your observations.Yes, air is coming out of all vents except defrost vents. Actuator directly behind glove box appears to be functioning normally.
Have you swapped actuators other than the one behind the glove box?
No I've never actually seen any of them fail. If you're able to switch between floor and vent then you know vacuum is at least getting to the selector switch in the dash. So more than likely your problem is either vacuum to the specific door that switches between vent and defrost, or the linkage for the door is bound or broken. You might be able to remove the ashtray and possibly some trim or cubbies or something. Different trim models and year models have different dash layouts so hard to say what it is you're looking at, but if you get a few things out of the way you might have a look at it from the passenger floorboard and see the linkage for the door.
Vacuum system seems good as pump only rarely kicks on and other vacuum driven vent components appear fine. Generalized schematic below,
Suspect the problem is as you surmised related to either motor #1, linkage, or feed line. Any idea where #1 actually is? Possible to service without removing the dash?
Like I mentioned you may get a look at it by removing the ashtray maybe pull the glovebox, but if you need really get hands on with it the dash has to come out. The way I remember it once you actually figure out where all the hidden screws and clips are it's not all that bad getting it out. I'm sure there's YouTube videos showing how to pull it.
Like I mentioned you may get a look at it by removing the ashtray maybe pull the glovebox, but if you need really get hands on with it the dash has to come out. The way I remember it once you actually figure out where all the hidden screws and clips are it's not all that bad getting it out. I'm sure there's YouTube videos showing how to pull it.
Pulled the radio to expose an actuator behind the radio (down and slightly to the right). Seems to have full swing and opens and closes a vent as it should. I am not seeing another actuator which opens and closes the defrost vent. Previously, switching to defrost would result in a "pop"or a "snap" noise that would be followed by a rush of air out of the vents. Sound seemed to be up higher that this actuator, closer to the actual defrost vent. Wonder where this actuator is and how would it be accessed?
Video of actuator behind the radio is here:
I found a thread that claims the floor defrost door actuator is below the back of the head unit about 8 inches down wrapped in insulation. Your video looks to be somewhat in that area but kind of hard to get context.
I found a thread that claims the floor defrost door actuator is below the back of the head unit about 8 inches down wrapped in insulation. Your video looks to be somewhat in that area but kind of hard to get context.
I've seen that thread as well. No insulation apparent in the area I am viewing. Found this:
Any idea where the "extension duct" is? It appears the actuator I am looking for is behind it. I have been going through my shop manuals, but remain clueless regarding where this specifically is... Update: "extension duct" is the plastic duct above the driver's feet. Removed it, and no additional actuator was apparent. I am beginning to think that this IS actuator #1, and the one behind the glove box is #17.
I may be able to help. I recently pulled my dash out to do a dash swap and had to modify the hvac box some. The actuator in your video is the one that moves the air from defrost to dash panel vents. Where's does the air come out of?
I this picture the actuator in your video is the same one on the side hete. The top big square hole is defrost and the other one that's foam blocking it is for the dash vents. The system defaults to defrost when there is no vacuum present.
I've seen that thread as well. No insulation apparent in the area I am viewing. Found this:
Any idea where the "extension duct" is? It appears the actuator I am looking for is behind it. I have been going through my shop manuals, but remain clueless regarding where this specifically is...
That is the actuator in your video. The extension duct is a extension duct for the driver side floor under the dash right abijt the trans tunnel.
That is the actuator in your video. The extension duct is a extension duct for the driver side floor under the dash right abijt the trans tunnel.
Yes. I agree. I have come to this conclusion as well. Interested in your thoughts regarding why I am getting weak air out of the defrost vents. As indicated,I used to hear the vent close with a "pop" when I'd switch to defrost.Don't hear this anymore and barely get air out of the defrost vents.Thanks.
Yes. I agree. I have come to this conclusion as well. Interested in your thoughts regarding why I am getting weak air out of the defrost vents. As indicated,I used to hear the vent close with a "pop" when I'd switch to defrost.Don't hear this anymore and barely get air out of the defrost vents.Thanks.
Does air come out of anywhere else when it in defrost? Dash or floor? Could be the other actuator. It sends the air to either the floor or the other actuator which send it to the defrost or dash. Kind of hard to guess unless you know exactly what it's doing and where the air is going and coming out.
Does air come out of anywhere else when it in defrost? Dash or floor? Could be the other actuator. It sends the air to either the floor or the other actuator which send it to the defrost or dash. Kind of hard to guess unless you know exactly what it's doing and where the air is going and coming out.
Moving through the selector results in air coming out of the appropriate vent, except that little air is coming out of defrost vents when that is the setting.
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