Hello,

I turned on the heater yesterday and noticed that the rear panel (roof) and floor vents did not blow hot air. It only blew cool air. The front system works well (both a/c and heater). I moved both rear system control ***** and there was no difference in temperature. The rear system does blow cold a/c air though.

Does the rear heater/ac system have a blend door? Is there anything else that regulates between the heater and a/c air?

Thanks!
zmanmikey

99 EB

 

I had a similar issue with my Expedition on a trip to Big Bear this past week. I have done a bit of research, and found these twoposts on another site that describe my situation almost perfectly. Just curious, do you get the clicking noise in the back right of your vehicle when you try to use the rear AC system?

Here was the first one I found...
"I have a noise with my rear air in my 02 Explorer. It sounds like a pump or something pulsating. Its a constant click, click, click. The engine does not have to be on, just the ignition. The rear air still blows cold. I pulled the panel off in the rear and it feels like its coming from a clear colored part behind the air unit. I unplugged the rear air to get rid of the annoying noise. When it started it would continue for about 30 minutes and then go away. Now it does not go away."

and here was a response to that from someone who seemed to knowmore about it...

"Just fixed my 2002 Explorer with this issue. You'll need part number #YL5Z-19E616-AA costs $86.06 + tax.

The box snaps apart by 2 plastic molded clips on each of the 4 sides. The gears had teeth that were indeed broken. I did some more investigation as to why this happened. The box is a simple DC motor / gear assembly with a wiper resistance pot to feed back position. The cars controller does not have the correct set points for the stopping points. This problem drives the motor even when the mechanical stop (flap is fully open or closed) is reached. This continued pressure strips the gears and causes the clacking noise. I have not dug into the controller to see if the end points can be
adjusted to turn off the motor at the end points."

Let me know if any of that info helps you. I am calling my mechanic to see if he can get a look at mine early next week, and I will post if I am successful.

 

Thanks for the post CD... I have the same problem (With constant clicking on 03 expedition)... dont know if the part no is the same but at least I know more about it now.. BTW Dealer in Col Springs estimated $400.

has anyone actually replaced the part yet? if so any luck finding/setting stops so it doesn't happen again?

more info in previous thread
https://www.ford-trucks.com/forums/4...light=thumping

 

I have not heard any clicking noises in the rear hvac system. I took the access cover off the rear hvac system (the one on the driver side-rear) to see if I saw a vent motor or something.

What I did see in the top-rear section of the hvac housing (where the blower motor is) was a set of wires going to some sort of "electronic card". This "card" slipped into some sort of plastic housing. What is this? What does it do?

Anyone else have this issue?

Thanks!
MM

 

I just had mine fixed by my mechanic, and when the work was all said and done, the final bill would have been right around $180 (the part itself is about $80 and the time to get it in there and install it,etc), but I had some other work done as well so the labor aspect of the bill makes that number an estimate.

The issue was fixed by the replacement of what turns out to be a small DC motor that is housed in what appears like a yellowish module with an electrical connection port. This same part also fixed my issue with not getting ehat to the rear as well. It basically controls the rear temp motor, etc.

There is no way to set 'stops' on the part though because it requires a small amount of tension on it at all times in order to work properly. When the part is working, there should not be any issue with noise whatsoever, but my mechanic said that the problem could reappear a few years down the road with the same part.

The funny thing of this is that it would seem to be a prevalent issue, because the first new part they put in (bought from the dealership) was also faulty, and they had to get a second one to fix it entirely.

 

It actually is fairly common problem. digging through a few past threads I found some great info from folks with the exact problem. sounds like Ford used the part on other vehicles with similar results.

My dealer estimated $400 to troubleshoot and fix. therefore I'm replacing my part today....removed it Sturday and ordered new part (45$ from Advance). It was a bear to get out and I anticipate some cursing when I replace it tonight.
There are two actuautors back there on an 03 expy...an easy one to R2 and a hard one to remove and replace....Of course I had the latter. I opened up the actuautor and its just a DC motor connected to a shaft via 3 very tiny plastic gears. one of which was stripped. I'm not planning on opening up the new piece but I suspect it has the same plastic gears and therefore subject to failure in the future. seems like brass vs plastic on the gears would fix.

I'll post in the next couple of days with a list of things I tore up replacing the actuautor! So far just one of the push connectors on the inetrior panel.

 

Got the actuator replaced and works like a champ. I now have heat in the back. Only suggestion is to pull the "shaft" portion from the old part and use as a guide for aligning the new part....it's very difficult to align if you dont pull the whole interior panel off.

Cheers

 

I just found the exact same problem.


Did you do it yourself??

 

yep, If you have thumping sound at certain temperature settings it's highly likely to be the blend door actuator. do a search in this forum for "+thumping +AC +rear" and you should find a couple of very good threads on proceedure. On an 03 model, it's not the easiest part to replace because of the location/access and you have to align the actuator just right when installing. but a 1/4" ratchet with a 5/16" socket is all you really need.

 

Just reaplaced my blend door actuator on the rear A/C of my 03 Expedition. Thanks Tater!!!!
Anyway I thought I would post my findings to save some others out there $200-$300. It's really not that hard! Note that there is an "Easy" and a "Hard" one in there.....Do yourself a favor and check the "Easy" one first and then move to the hard one.

Tools Required: 5/16" socket (small driver is better than larger in my opinion), phillips screwdriver, Torque head socket, and maybe a flathead to jimmy the trim off in some spots.
Parts Required: Got mine from Oriellly Auto Parts ($34) it's a Dorman Heater Blend Door Acutator Part # 604-202

"Easy" One
1. Simply Pop off the Long Change/crap holder underneath the rear passenger side glass. (Snaps right out with a little pressre but be careful).
2. Turn on your car and adjust the Rear A/C until you hear the thumping.
3. You will see the Rear A/C unit and right on top is an White/Opaque square box. Unplug the wiring harness from this box and see if it stops. If it does you are in luck! If not see "Hard" One
4. Pop out the cup holder just in front of the open trim hole (you will need to to get another hand in there)
5. Use your 5/16" socket and remove. Place the new part in it's place.
6. Make sure you align the pin (Do this by pluging the wiring harness into the new unit and have someone adjust the Hot/Cold until the pin lines up and the new actuator slips in correctly and the bolt hoes line up.
7. Bolt in and Test....Replace the trim and you are done.

'Hard" One
1. Do above precedure until step 3 if the thumping does not stop put the wiring harness back in "Easy" one and locate the 2nd actuator which is a little farther forward and along the side next to the trim. Disconnect that wiring harness and verify the thumping stops. If it does not stop...Sorry you are SOL for this thread. If it does stop, make sure you have a couple hours to devote to replacing this. If you don't just leave it disconnected until you have time (at least the thumping has stopped but you will likely have drastic temps in the rear)
2. Now you basically need to remove the rear trim panel enough to get the space to remove this unit.
3. Below is the order I would take the trim off...Just need a little force to get the clips out
A-remove the spare tire lid, and jack
B- remove the skid trim
C- remove the black jack liner 5/16" socket and a rubber gasket and it snaps out
D- remove the top center trim
E- Use Torque head socket to remove the top seat belt bolt
F- unscrew the plastic screw which hold down the rear panel trim "ear" to the frame
G- snap off the upper Corner post trim enough to get the rear panel snaped out
H- snap off the rear panel enough so you have some room to work (there won't be much but there is enough to get in there) otherwise you will have to take the entire panel off which I did not do.
4. Unbolt the actuator 5/16" socket Qty 4
5. Place the new part in it's place.
6. Make sure you align the pin (Do this by pluging the wiring harness into the new unit and have someone adjust the Hot/Cold until the pin lines up and the new actuator slips in correctly and the bolt hoes line up.
7. Bolt in and Test....Replace the trim and you are done.

Took me about 2 hours becuase I was scared i would tear up the trim and thought the whole panel needed to come off but now I could do it in about 30-45 minutes.

Danny

 

Great post Danny!

 

On the O3 and up you need to isolate which is making the noise. If you dont have an assistant the best way is to use the controls. Start the vehicle with the rear system working and while the popping noise is occuring, adjust the temp control to the opposite direction, hot or cold and see if the noise goes away or at least changes. If it doesnt switch the mode to floor and back to roof several times. If the noise goes away or at least changes sound then that is the mode control actuator (the easier one to replace).
Only caveat to that is that sometimes I get vehicles in where BOTH of them are popping and BOTH need replaced.
Also if they are real bad they may not stop or change sound at all because the gear is stripped out bad. Of course that should only be the case if you let it go for a long time before doing anything about it.

tatetodd I dont know how your dealer came up with 400.00 to fix it. Worst case scenario at my dealership might be 250.00.

 

great recap DR!

400$ was an estimate.. said he'd know more when he found out what the problem was. I found enough threads here to fix myself, So I never did get a quote... sounds like 200-300$ is average of those that posted in past. I hadn't seen anything on the double whammy actuators. Thats good info.

I've had better luck with other dealers and my uncle has worked for Ford MX for years in the southeast. I think I'll head down the road to another place If I have other issues.

Homer, do you know if the replacement parts any better than the original or is it the same plastic gears?

 

Homer, do you know if the replacement parts any better than the original or is it the same plastic gears?
__________________

They have been pretty much the same for years and years. Might have found a better vendor but no promises.

 

Dr. Thornton was right on. I appreciate the details. It took me less than an hour. $50 at Napa for the part which works for either failed component, at least on my 03. Part number a little different at Napa, but they can pull it right up (dont have it on me). The part I got was black and still had plastic gears. The actuator farther forward controls the door for the floor vents while the one farther aft and on the side is for the roof vents. I had a little trouble getting it to go in, not just from the line up but it fit more snuggly. I filed ever so little and greased it so dont be discouraged if you think it is lined up (by comparing the one you remove with the one you are replacing) and it doesnt go right in. Dont mess with the temp control while you are doing it that way. Also, I did it by myself with the units unbolted and moving the temp control a little at a time until they fit. Make sure the plug is in well. I goofed up and one plug came unseated while I was testing it and I thought it still didnt work. Stupid mistake but everything worked just as advertised. Make sure you have that torx head before you start for that rear seatbelt. Fortunately I found mine and wasnt delayed. You need to switch between floor vent and roof vent to line up each actuator if you had them both out. Took me a few minutes to realize that