Noise from under my dash

[Backwoods Rambler]

Can anyone help me with what this noise would be? I don't hear it all the time, but there doesn't seem to be any specific trigger for it either.

Link, in case you missed it eep:https://youtu.be/eNiYdrgQ4e8

Thanks,

 

[AuSeeker]

Need more info.

Just help anyone with trying to deduce what the noise is, when does this noise occur, when you turn on the ignition, start the engine, when the AC/heater is on, when you depress the brake pedal, or any combination of the aforementioned, or....etc., etc., is there any time that the nosie stops?

 

[TowMeOut]

Just a wild guess but since you have a limited I think that means you have the dual zone AC setup. It's pretty common for the various air mix servos to start going haywire with age. Do some searches for "servo" or "air mix servo". You'll find a lot of threads about how these start to "hunt" over time because the inside contacts get dirty and send false readings to the computer. The servo starts tracking back and forth erratically while the computer tries to compensate.

I'm not sure on the limited but you should be able to set the temp all the way to the "LO" setting and operate the fan speed manually (take it out of AUTO) and see if the noise goes away. If so, I'd say that's your culprit.

I haven't seen many threads on fixing the driver's side servo. However, the ones about dealing with the tight spaces under the driver's side dash should give you some ideas. To remove/install.....it's a huge pain in the butt.

Good luck!!

 

[AuSeeker]

Just a wild guess but since you have a limited I think that means you have the dual zone AC setup. It's pretty common for the various air mix servos to start going haywire with age. Do some searches for "servo" or "air mix servo". You'll find a lot of threads about how these start to "hunt" over time because the inside contacts get dirty and send false readings to the computer. The servo starts tracking back and forth erratically while the computer tries to compensate.

I'm not sure on the limited but you should be able to set the temp all the way to the "LO" setting and operate the fan speed manually (take it out of AUTO) and see if the noise goes away. If so, I'd say that's your culprit.

I haven't seen many threads on fixing the driver's side servo. However, the ones about dealing with the tight spaces under the driver's side dash should give you some ideas. To remove/install.....it's a huge pain in the butt.

Good luck!!

That was my first thought as well but figured a bit more info was needed to confirm if it's that or not.

 

[Tigerfan95]

I have this exact sound coming from my dash too, and it sounds like it's coming from behind the glove box. I have the sport edition though, so I don't have dual climate control.

 

[jdc62]

What you're describing sounds like the same issue I had last fall. It turned out to be a failing Damper (or Mode) servo. It's the servo that controls the door that directs the vents to defrost. I was able to replace mine and it solved the problem. There are other servos on the HVAC box but this seems to be the one I've seen most thread about. See the link below.

http://www.toyota-4runner.org/4th-gen-t4rs/239316-servo-sub-assy-damper-replacement.html

 

[Backwoods Rambler]

Thanks for the tips everyone. I never use the AUTO climate control mode, so I'm leaning towards what jdc62 is suggesting.