Well I though it was only EATC, but it appears manuals have a electric actuator motor that is addressed below. Here's what the TSB addresses:

EATC—INTERMITTENT WARM AIR OUTPUT TSB 08-23-6
TEMPERATURE SET 68-72 F (18-22 C) EMTC—INABILITY TO CONTROL TEMPERATURE OUTPUT
FORD: LINCOLN: 2005-2008 F-150 2006-2008 Mark LT

ISSUE NOTE
Some 2005-2008 F-150 and 2006-2008 Mark LT vehicles equipped with Electronic Automatic Temperature Control (EATC) may exhibit intermittent periods of warm air output in Auto mode with the temperature control set between 68-72 degrees Fahrenheit (18-22 degrees Celsius). Some 2005-2008 F-150 vehicles equipped with Electronic Manual Temperature Control (EMTC) may exhibit periods where the cabin temperature cannot be maintained with the control ****. Some customers may also complain the heat cannot be reduced without rotating the control **** well into the
Cool/Blue range.

WARRANTY STATUS: Eligible Under Provisions Of New Vehicle Limited ACTION Warranty Coverage


I never have good experience with warranty work, so I replaced mine myself. It's not a difficult job, but access is extremely tight. The part is about $25 and it's part no. 9L3Z-19E616-E Actuator - Motor Asy. Ford allows dealerships 1/2 labor for the warranty repair. Removal of the radio and glove box door are necessary for the replacement.

 

Great info thanks, I'm buying the part today, sick of this issue.. Anything else of note with the repair, I know how to get to the radio and glovebox, anything else tricky or that I'm likely to break? Not asking for a full pictorial step by step, just the normal warnings about weak tabs that break or easier methods to get to the part. Thanks!

 

There is a wiring harness that runs on top of the actuator. If you pull the harness from the mounting tabs it makes it easier to access. Because access is so tight you need a small wrench as a socket won't work for all the bolts. I used a small ignition wrench, but I don't recall the size. The motor basically lifts up after the 3 bolts are removed. Just reverse to install.

 

Fish let me know what happens b/c I'm having the same issue.

 

I have the manual A/C controls and had the same problem. I lived with it for a couple of months then finally took it in and got it fixed. It's been working good so far.

 

Stopped at my Ford Dealer today with the TSB information in hand and made an appointment for tomorrow morning.

I will let you know how it goes.... My truck is still under warranty until April 28th..........

 

Windsor nailed it: 9L3Z-19E616-E was the part number and he described the install perfectly. I did not end up touching the large harness, just left it in place and went about the business of removing the part. The wrench needed is an 8mm combination wrench, a socket/ratchet wont fit even with a wobble bit. An 8mm gear drive combo wrench works perfectly to do the numerous turns to remove the 3 screws in the tight confines of the under dash area. Use the open end to start the near bolt, and flip to the closed gear drive side of the wrench to back it all the way out. The other two bolts don't require the open end, the are accessible enough to get the whole wrench over the bolt. When you start the truck you have to go full hot/full cold 1x (60-90-60) and then it starts working right.

 

Back from the dealer with a new 9L3Z-19E616-E Actuator - Motor Assembly installed under Warranty. The heater temp control now works like a champ. In fact, it has never worked this way since I picked up my used truck in July.

Thanks all for the info provided. It was most helpful!!!

 

I have an '08 XLT with the same problem. I have 60,000 on mine so it is out of warranty. Anyone pay the dealer for this repair? How much will I be likely to spend on this? Thanks

 

Since the part is $25 and Ford only gives the dealer 1/2 hour of labor for warranty, I can't see that it would be more than $100.

 

I just took mine in for this problem and the dealer quoted me $700 for replacement of the HVAC actuator motor control assy! I crawled under the dash, drivers side, the part was clearly visible, on the side of the plenum just to the right of the gas pedal.