What part is this? (Buzzing from Air Conditioner)

[balladbeach24]

My blower motor was starting to go out - sometimes it wouldn't come on at all, and I had to smack it with something in order to get it to come on. This went on for a few weeks before I could get around to replacing it. Well, shortly before I purchased the new one from Advance, I started to notice a severe buzzing sound that would go for a few minutes, and then shut off, only to come back on a few minutes later.

I replaced the blower motor, and when I went to start the truck, it was doing it again, while the truck was in ACCY mode, before I even started it, and it does it sporadically, sometimes before the fan even comes on.

I dug around some more, and I think I've found what it is, but in looking for an exploded diagram of behind the glove box, I can't find out what it's called.

If anyone can help me identify this, I would certainly appreciate it. I think it's the air mix servo, not sure.

Thanks in advance.

 

[techno]

I think it's this thingy.

...

 

[BlackWorksInc]

You're sure that it's the servo motor for the "Mode" and not the recirculation (on the right side of the blower box)

Does the issue get better, worse, change at all if you select different modes (i.e. vents only, both vents, floor only, defrost, ect.)

The issue is that you're gonna have a tough time getting that actuator out, At best you can get it if you take the dash off, at worst you might need to partially disassembly the HVAC assembly to get it off completely (which means pulling the HVAC box out to get access to the screws.)

It's been a while since I had to deal with one of those so I don't quite remember if you can "flat rate it" or not.

 

[techno]

I'm not totally sure. I just found what I think looks like the part in his photo, then Google imaged the part number to check. Either way both part numbers are shown so that should help.

 

[BlackWorksInc]

I'm not totally sure. I just found what I think looks like the part in his photo, then Google imaged the part number to check. Either way both part numbers are shown so that should help.

You have the part in the picture highlighted correctly. I am just curious if that's where the noise is originating from.

 

[00_4runner]

You're sure that it's the servo motor for the "Mode" and not the recirculation (on the right side of the blower box)

Does the issue get better, worse, change at all if you select different modes (i.e. vents only, both vents, floor only, defrost, ect.)

The issue is that you're gonna have a tough time getting that actuator out, At best you can get it if you take the dash off, at worst you might need to partially disassembly the HVAC assembly to get it off completely (which means pulling the HVAC box out to get access to the screws.)

It's been a while since I had to deal with one of those so I don't quite remember if you can "flat rate it" or not.

Mine makes the funny clicking noise I've read about on other threads... It makes the noise while on every setting except defrost and face only. So yes, changing the mode can resolve the issue. Does this mean the recirculation part?

 

[BlackWorksInc]

Mine makes the funny clicking noise I've read about on other threads... It makes the noise while on every setting except defrost and face only. So yes, changing the mode can resolve the issue. Does this mean the recirculation part?

Face setting probably will not have much to do with it, but Defrost is typically automatically set to "fresh air" setting if I remember right.

What you can do to isolate the issue is turn on/off re-circulation and listen if the clicking goes away. If it does when you turn it on/off then it's most likely that. If not, then the mode door actuator could be the issue.

What's clicking is that the actuator doesn't know where it is anymore and keeps trying to close/open itself when it's already at maximum movement.

 

[heatherlrader]

Air stuck on Face only & Noise

Hey, after googling for a few hours I found this thread. My '07 starting making the loud noise in August (it always had a small clicking noise like maybe debris in the fan under the filter but it was getting a little louder before the new noise) and I noticed it comes from the drivers side and the passenger side various times and situations. The air will stay on face vent only and if you try to change it to another vent or change the temperature it makes the noise from the passenger side. I am trying to figure out if this will be a fix I can do myself in a day, is the mode servo easy to replace for someone who's never removed the dash? If so do you think I need to take out the servos on both sides and fix the pins as well to fix the noise? Its going to start getting frosty soon and I wont have a way to defrost my windshield. Thanks!

 

[BlackWorksInc]

Hey, after googling for a few hours I found this thread. My '07 starting making the loud noise in August (it always had a small clicking noise like maybe debris in the fan under the filter but it was getting a little louder before the new noise) and I noticed it comes from the drivers side and the passenger side various times and situations. The air will stay on face vent only and if you try to change it to another vent or change the temperature it makes the noise from the passenger side. I am trying to figure out if this will be a fix I can do myself in a day, is the mode servo easy to replace for someone who's never removed the dash? If so do you think I need to take out the servos on both sides and fix the pins as well to fix the noise? Its going to start getting frosty soon and I wont have a way to defrost my windshield. Thanks!

Not sure you can fix the "pins" I just replaced the A/C Amplifier (Air Conditioning Control Module) and Recirculation Door Actuator in a '08 Land Cruiser today for a similar issue. The actuator was clicking/making a knocking noise like someone at the door constantly because the "position circuit" failed (not sure if that took out the amplifier because they didn't fix it, or if the amplifier took a shit and the actuator failed coincidentally). That particular actuator (different actuator part number/design than 4Runner, but similar principle) used a sealed ring on the plastic differential inside of the actuator to determine position; you wouldn't be able to "clean/repair" that particular circuit so it's junk (well I mean the motor was still good so I scavenged that lol)

As for replacing it, depends on the actuator; some of them are easy to get to, others may require the removal of the entire dash if not the HVAC cluster on some vehicles. It's been a while since I had a 4Runner Dash off or looked at the actuators so I am not entirely sure how hard it'd be. You could probably get the one on the Driver's Side easily (Item 87106D in the Diagram) and the Recirculation Actuator (Item 87106G in the Diagram) is a bit of a pain in the ass but doable without removing the dash (I have a write-up for that somewhere). But the mode actuators located on the side of the HVAC Housing (Items 87106J & 87106L in the Diagram), those you may have to pull the dash off to have good access to, if not remove the HVAC assembly to remove the blower housing from the HVAC core to access the actuators properly. If it's similar to the Highlander and Prius units I've have to replace/tear down & clean for rodent issues; those two actuators cannot be removed easily if at all without having the HVAC assembly on the bench and the blower housing removed.

Shamelessly borrowed [MENTION=9776]techno[/MENTION]'s Diagram.

 

[duffdog]

It can easily be fixed, I have already done it.

check this out:

http://www.toyota-4runner.org/4th-gen-t4rs/226022-weird-dash-noise-2007-v8-sr5.html#post2485116

 

[BlackWorksInc]

It can easily be fixed, I have already done it.

check this out:

http://www.toyota-4runner.org/4th-gen-t4rs/226022-weird-dash-noise-2007-v8-sr5.html#post2485116

Your assumption is not entirely accurate, it COULD be the worm gear; the more common issue I have seen is the position sensing circuit is faulty/worn and the motor doesn't know it's Open or Closed and continues to try and close/open the door when it can't.

Additionally it depends on which actuator you're talking about it being "easy" to get to.

 

[duffdog]

Your assumption is not entirely accurate, it COULD be the worm gear; the more common issue I have seen is the position sensing circuit is faulty/worn and the motor doesn't know it's Open or Closed and continues to try and close/open the door when it can't.

Additionally it depends on which actuator you're talking about it being "easy" to get to.

They are all easy to get to with the proper tools. Even the "impossible to remove" actuator next to the blower on the passenger side. I have removed and repaired it in 1 hour. You just have to be creative and use some right angle screwdriver tools.

 

[BlackWorksInc]

They are all easy to get to with the proper tools. Even the "impossible to remove" actuator next to the blower on the passenger side. I have removed and repaired it in 1 hour. You just have to be creative and use some right angle screwdriver tools.

I was just looking at a newer 5th gen's HVAC box which I assume is similar, it looks like once you get the AC Amplifier out of the way you should be able to get the carriage that holds the two actuators off with some IKEA Furniture style ratcheting right-hand screw drivers.

 

[heatherlrader]

Thanks! I believe I'll have to try tinkering with it in a couple of weekends and see where that gets me.

 

[toyo]

Mine has the PITA clicking noise. Currently it only does it on the dash/face setting. If I move it off that setting at all it stops.

 

[heatherlrader]

Fixed!

Thank you all for the helpful info! I finally got the nerve up to tackle the project and surprisingly fixed it (with only minor cuts to my fingers)! The worm gear was loose and just needed a couple of taps to get the space closed. The part was a little different from the diagram. The video helped a lot but getting it in and out took some swear words and sliced fingers. My hubby would've never gotten his hands in that tiny space! Just wanted to say thanks and show the worm that was causing the buzzin noise. I was very happy to have the defrost and feet vents working again!

 

[toyo]

Which actuator did you remove? Mine is definitely the Air Inlet Damper Control Servo Motor. Of course its the PITA one. You can be sure that if I have to pull that dash out to remove the blower sub assembly that I'm gonna put in a new evaporator. My luck mine will develop the infamous leak in 6 months.

 

[heatherlrader]

Which actuator did you remove? Mine is definitely the Air Inlet Damper Control Servo Motor. Of course its the PITA one. You can be sure that if I have to pull that dash out to remove the blower sub assembly that I'm gonna put in a new evaporator. My luck mine will develop the infamous leak in 6 months.

The one in the pics at the beginning of this thread is the one I removed and fixed. There's another one below it and I know I wouldn't have been able to get to that one.

 

[toyo]

I replaced the servo motor today. It was part 87106-35120. It is the far right one in the back. Like Blackworks stated the FSM states to remove the dash panel to replace it.
Once you remove the glove box and the upper storage box you will have full access to the ECM on the right side. The ECM sits in a metal cage with a nut on the bottom and 2 nuts up top. Very easy to see them. Remove those 3 nuts and pull the ECM down towards the floorboard so it's out of the way. You will now have full access to the servo. The photo shows the ECM moved out of the way. There's 2 screws that holds it in. Top right and bottom left. The top right screw is a little more difficult but 100% doable. Once you have the old servo out compare the arm position with the new one. If the are not in the same position move the linkage on the evaporator, NOT the new servo motor. It will either be in the Fresh or Recirculate position when you remove it. I can't remember what position the new one was in but I did have to move the door linkage.
Almost forgot. Disconnect the battery without hesitation. You will working around and moving the ECM and such so it's always a smart thing to do.
I hope this helps with anybody that needs to replace this certain servo assembly.

 

[eric.chambers.180]

I have a humming noise that starts when the key hits the accy position. There is no chance in the noise when the HVAC system is turned off. It appears to be coming from under the dash also. Any thoughts?


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