Removing the A/C blend door actuator

Thanks for posting this. I'm having a very similar issue but with my gen 3 Prius. However I was seeing a cog wheel click (it seems off the track or something) on the passenger side near where you are in your video. I'm wondering if I need to do something on the passenger side? Like you, I haven't been able to find out how to get to the part exactly. I'm also not sure if the gen 2 and 3 Prius are the same in this regards.

 

I think Gen 1 and Gen 2 had somewhat similar heaters, with the air mix actuator and outlet select actuator over on the driver's side, and only the fresh/recirc actuator smushed between the heater and blower case on the passenger side.

Gen 3's case is a much different shape I think, with at least two of the actuators, maybe all of them, over on the harder-to-get-to side.

Gen 3 also has a different actuator design. Gen 1 and 2 sensed position with a simple resistive potentiometer kind of sensor that could get noisy (in the electrical sense) and respond well to cleaning; I think the ones in Gen 3 are more of a Gray-code kind of arrangement, and should stay trouble-free a lot longer.

-Chap

 

How did you get the top screw out? There is no clearance. Did you remove the other modules around it?

My dash is apart today for installation of a new combination meter board (no more 299,999 mile limit...bonus) and I'd like to address the actuator motor while I'm working in it.

Paul A.
Palm Beach Gardens, FL
288k 2004

 

Bless your soul for posting this video, I have the EXACT same sound happening in my car and your video will be extremely helpful trying to fix this thing! If I may ask, what did you use to clean and re-lubricate the mechanism?

 

I don't know what yitz used, but I used a stuff from GC called Jiffy Bath.

When you get the thing apart, you're likely to see that there's no lubrication problem. What makes these things do what they do is dirty electrical contact between the springy metal fingers and the resistive paths you see on the big driven gear, which are how the position feedback gets read by the controlller. Poor contact makes the "position" appear to be jumping around (when it really isn't), which makes the controller keep sending motion signals trying to hold it still (which makes it jump around).

Any electrical contact cleaner on those areas will clear it up; Jiffy Bath includes a light lubricant film that may reduce wear from the contact fingers as it moves around.

-Chap

 

Does anyone have an visuals on where the blend door assembly is on a 2010? I have no heat even though the two coolant hoses goign into the back of the engine compartment (behind dash) are both hot. Since air is blowing bit is barely luke warm, I figure the door must not be allowing air to blow across the heater core.

 

Well, this is a thread in the Gen 2 forum and you're asking about a Gen 3 ... they moved both the air outlet and air mix servos over to the right side of the heater case for Gen 3, right where you would not want them, sandwiched between it and the blower case. Because of the difficulty of getting to them, I would definitely do all the diagnosis I could by other means at first, and only dig in there if the actual verdict was I had to. With Techstream you can tell them to move at will and also read back their position indicators, and you can read the cabin temperature sensor too (sometimes a "no heat" issue is just because the A/C amplifier doesn't think you need any heat).

-Chap

 

Thank you
I have been quoted a large sum of money for Toyota to even begin the procedure of confirming that it is the “upper blend door motor binding” because they would have to remove the whole dash. How did you ascertain that it was the door blend actuator? Is there just one on the driver side? I was told that the problem is a part of a $5000 part most likely. Though to me it sounds like what you dealt with.

 

Did you have to remove the whole dash? I rewatched the video and I could not tell.

Again, thank you very much for posting,

Chris

 

I ran into the same problem with the noise on my 2006 Prius. You don't have to tear apart the dash. Its right below the dash by the accelerator pedal. I bought the low profile screw drivers as suggested (from Amazon, $16). Too a bit to wrestle the screw out, but once done, it was pretty straight forward. I found the best way to do this is as follows:

1) Once you get the unit out, take a picture of it, noting the way the arm is "indexed" within the module. Its important, as you will need to put the arm and gears in the exact way it was before disassembly.

2) Be careful when taking the module apart, as the tabs are likely dried out and will snap off (which is what happened to me), requiring some other way to hold the unit together (I had small tie-wraps to do the trick).

3) Once opened, take out the biggest gear and flip it over. You will see part of the potentiometer assembly, with the resistor material that is likely where the problem resides.

4) Use a q-tip to clean off the grease and old worn material. You should see where the finger wear is on the resistive material. Be careful to clean off the fingers on the other part of the potentiometer. Wipe off the resistive material completely, then use some of the excess grease nearby (there's always some on other parts of the assembly) and apply it to the resistive material using another q-tip.

5) Reassemble the unit noting the exact index as in your picture that you took before disassembly.

6) I used small tie-wraps within the 4 holes to secure the assembly, as I broke all of the snaps during tear-down.

7) Make sure you line up the module arms with the slot in the doors (there are two).

8) Secure with the two screws (honestly, I was lazy and only secured the easiest screw, but it seems to work fine).

9) Reconnect the electrical plug, turn on the car and test the various heater and AC options.

 

Hi as I too have the same sound. I thought it should be the one you have taken apart.

But mine seams to be another one, one step over yours?

if i lay my self on the floor and look up where the gaspedal is, i first this one you have taken down. But above that one there is another one. Whats that?

because i think that thats my problem. Not the one with the screw on the picture. The next one with the white arm on the outside (left).

i have à video of it ”snapping” but i dont know How to uppload it here from my mobile

 

Sorry for a double post. But here is a video of mine.

 

For some reason, this seems to be HVAC Actuator Week.

For an illustration of the three servos and their locations, you can view this other recent post.

 

Anyone successfullly got the blend door actuator out?
The one above the doorblender(the one Above the one yitznewton took out in his video)

 

Would a faulty blend door actuator explain why the two right vents blow cold, while the two left vents blow warm? we don't have dual climate zones so should I even be looking at the blend door actuator?

 

No, there is only a single air door and actuator for temperature control. 1st guess for only some vents blowing cool is that there is a leak somewhere in the refrigerant system and you are low on charge.

Posted via the PriusChat mobile app.

 

Thank you- I know it is a sealed system but for a car that is 13 years old, is it possible it has just lost some coolant overtime and a recharge should be all I need? I am just hoping for best case scenario and not a leaky coil