Vent Cycles Between Fresh and Recirc (1 Viewer)

Joined
Jul 2, 2004
Messages
21
Location
BC Canada
 
 
Wifey informed me today that we have a new noise in the LX. Seems that the HVAC fresh air vent is cycling open and closed continually in the "Fresh" position. "Click, whirrr, click, whirrr, click, whirrr". If I switch it to "Recirc", it is quiet. I played with all the setting on the beloved Auto Climate Control, but to no avail.

I have no idea where to start troubleshooting. I can keep the vent in the recirc position for now, but the windows sure fog up quickly.

I also checked the vent to see if the Lexus' pink panties somehow got caught in there, but it looks clear.

Has anyone ever heard of this problem before?

Click, whirrr, click, whirrr, click, whirrr, ARGGH!! :crybaby:
 
Joined
May 26, 2005
Messages
7,782
Location
Phoenix
 
 
 
I've seen this in other cars, I believe the vent functions are vacuum powered, and you may have a leak or bad actuator diaphram. I'm sure someone here will know if that's it.

-Spike
 
Joined
Jul 2, 2004
Messages
21
Location
BC Canada
 
 
Spike, thanks for the response. I am digging into the dash now, and it appears to be all electronically activated.

I apologize in advance for not having the FSM for the Lexus, and will rectify asap. Also, no TIS access from Canada :frown:

For now I am hoping someone can help me check something. I removed the vent actuator from under the glovebox. It opens and closes the vent continually when I press the fresh air button. I need to know if the actuator connects directly to the HVAC control unit, or if there is a sensor somewhere inline. The p/n of the actuator is 063700-2681 and the three wires connecting it are yellow, blue/white, and solid blue.

I understand it's a pain, but if anyone can help, thanks! If not "No Worries!"...will have to wait for my FSM :cool:

Mark
Vent 002.jpg
Vent 003.jpg
 
Joined
Jul 2, 2004
Messages
21
Location
BC Canada
 
 
I found a Tacoma manual online, and I am reasonably sure the "air inlet control servo motor" is connected directly to the "AC Control Assembly". Am 90% sure this is my problem. Will get a price on it and decide whether to troubleshoot further, or do the swap out and hope it works! For now I have it disconnected in the "fresh" position, so I am good to go.

Thanks for letting me ramble!

Mark :cheers:
 
Joined
Nov 16, 2003
Messages
6,045
Location
Dixie co. Florida
 
accordign to the 96 LX450 ewd The "air inlet control servo motor" connects to the "ac automatic amplifier" witch is a separate part from the "AC system amplifier". It also connects to a jumper block I donk know why.

If I were to make a guess I would say the limit switch for the fresh position in the survo motor is open. you may be able to dissasemble it an fix it.

PS I can get you eiter of those parts or both from a 97,
 
Joined
Jul 2, 2004
Messages
21
Location
BC Canada
 
 
Thanks RavenTai. I would agree that the limit switch is open. This servo should rotate half way around, and then back. This switches it between fresh and recirc. Mine goes around in a complete 360 degree circle, opening and closing the whole time. I had it apart and cleaned the contacts a bit, but it didn't help.

New part lists at over $140 (minus the C-Dan discount - thanks Dan). A little more than I was hoping to spend. Might be worth cleaning it up a little more carefully and trying again.

(RavenTai, will PM you re: the parts you have.)

Mark
LX450 Vent 012.jpg
LX450 Vent 013.jpg
 
Joined
Aug 1, 2006
Messages
10
Vent Problems

Not meaning to highjack this thread, but I am new to the 80 series luxury and am suffering some HVAC issues to. My 92 barely pushes air out of any of the vents -particularly cold air out the defrost.

The fan seems to work fine, and it doesn't matter if it is recirculating or fresh air (front cowl seems clear of debris and the fan is working)

I have the dash mostly apart and everything seems ok connection wise.

there seems to be a water leak of some kind by my left foot but I don't see how it could be related.

Were to start ?
Thank You
 
Joined
Nov 16, 2003
Messages
6,045
Location
Dixie co. Florida
 
two common sources of water leaks are clogged sun roof drains and leaking windshields, mine was a windshield. search on windshilds if you have one replaced the installer needs to use sealent, many seam to think when there is a gasket none is needed and the result is a leak,

on the low airflow I would start by pulling the fan and checking for debris, leaves and rat nests are common air flow cloggers
 
Joined
Jun 27, 2005
Messages
316
Location
Austin, TX
the OP hasn't returned to the boards in a long time. I still have this buzz-click issue myself and was wondering if anyone else has solved this?
 
Joined
Jun 27, 2005
Messages
316
Location
Austin, TX
Top Gear fixed his restless servo motor by replacing it with a used one.


are you having the same problem?
Yes! Whirr, click, whirr, click, constantly while the air is set to fresh air rather than recirc. It drives me nuts!

I'm just glad I know what solves it now so I can go about sourcing a part. You wouldn't happen to have another to sell, would you? :D
 

Users Who Are Viewing This Thread (Users: 0, Guests: 1)

Top Bottom