Lost all vent controls???

Seems I lost all my vent controls. In all modes: nothing from the defrost vents; I get more to floor when hot, more through the vents when cold.

All the vacuum lines under the hood are good... and the feed must be good since my cruise still works.

Where to look next? Line break inside the dash somewhere?

Did some more checking... Seems the issue is the vent/defog door is stuck in the vent position and has broken from it's rotator shaft. The floor valve is working as intended... but the vent/defog arm moves as it should, but the air flow doesn't follow.

Common issue? Can it be accessed from under the dash pad, or will I need to pull the entire dash? I have factory AC, if it matters.

(I'm on a work trip this week... so I have time to figure this out).

Check this out

Very common issue that a lot of us here have addressed by necessity or as preventative.

The guide above is great but if you have any questions let us know. I did mine out of dash but I can think of a few here that did it in dash.

Yep, good ole blend door repair. Everyone who owns these trucks and desires to keep them maintained will see this. The gentleman who posted that up did an exceptional job putting that together. I pretty much followed his instructions but pulled the dash out further so I could remove the vent work and have good access to the door. It's not that bad of a repair.

Yep, going to follow this one as well.  I have defrost and floor, but no panel vents.   Wanted to see if I could get that fixed before having the rest of system checked and charged.  

Duh. Should have searched first...

Looks like I have some fabricobbling to do. and a hinge to order...

Got the job done.

I used a slightly different approach... as it turns out, with some fiddling it is possible to remove the passenger side vent duct... but I cracked part of the dash in the process :



Thankfully it's well hidden by the dash pad. I drilled the end of the crack to prevent it from spreading.

I also took a different approach to the hinge itself. Instead of bending it in a vice, I used a punch to remove the entire hinge pin (after cutting the hinge to length) and flipped one side so when open, the hinge isn't flat, but stepped (should have gotten a pic, if you all want, I can do the same with the extra hinge section I have). I then had to cut down the hinge again because I forgot that by flipping the hinge (and cutting the hinge to a length where each half had the same number "fingers"), the end cuts would offset and cause an fitment issue. Still worked out, but I had to omit a fastener on reassembly. This made the hinge bit a tad too long, which was good, since that allowed me to peen the ends to ensure it doesn't fall out of the hinge over time (the pin wasn't peened or crimped from the factory)

I also had issues with the old rivets spinning. Ended up using the alignment peg holes instead for re-attachment (I drilled them out on the old piece to use as a template).

Door installed:



I used wide-headed 1/8" all-aluminum rivets for the hinge attachment. I find the bigger rivet heads work better on plastic... and since I was ordering from McMaster, wasn't that expensive to order a box to have on hand.

My foam seals were still good, so other than breaking loose the back row of anchors on the side I riveted the hinge to, didn't mess with it.

So far, it works great... no significant leaks (maybe a hint of flow out the vents when on floor/defog, but that's on full blast and I can barely feel it). Better than it's ever been since I bought it.

Sorry to hear about the crack but at least it is hidden.
AND everything is back to working

Flipping the hinge is what I did as well and works great

Well done, save for the crack.  That approach must be easier than the way I did it in situ.  Man, that is painful and I had the cuts to prove it at the time.  Hope I don't have to do another, but I'll try your approach if I do.

If you do, good luck not cracking the dash... I'm not convinced that this method will work without it (or removing more dash panel anchors). To do what I did, you'll have to remove (in addition to the fasteners in the procedure linked above) the dash pad, the dash anchor bolt by the passenger bottom corner of the windshield, the two dash panel anchor screws above the radio/clock bezel (attaches to the AM speaker bracket), and the AM speaker if equipped. There also is a single screw from the top that holds the two duct sections together that will also need removed. Flex the dash panel forward, and the duct should swing out of the way. Not a fun process, but it gives so much better access to the door. This also allows one to do a functional test before final reassembly.

I've been close to that point several times of late.  I've had the dash pad off enough times to be able to count the screws in my head.  As well as the speaker bracket.  And while I was there I checked the tightness of the dash anchors screws.

So it isn't that big of a deal compared with what I went through the way I did it.  And, as you say, it allows for testing.