Update:

Brought the car in to my local Lexus dealer and explained the issue to them. They seemed reluctant at first, having a hard time believing the issue, saying they've only had to replace Servo motors on A/C-On related temp issues, not A/C-Off. 3 guys that I talked to all said the air "felt normal"....but I knew it was not normal...hasn't been since day 1 and I'm going on 3 years now). After a back and forth with various employees trying to convince them that's it's a real issue, the Service Advisor/Manager guy got his Tech to plug in their Snap-On diagnostic computer and they found 3 stored diagnostic codes. I had no idea the computer even stores these codes (separate from CELs), so that was interesting.

B1453: Air Outlet Damper Cool Control Servo Motor Circut (Driver Side)
B1454: Air Outlet Damper Cool Control Servo Motor Circut (Passenger Side)
B1455: Air Outlet Damper FOOT/DEF Control Servo Motor Circuit (Driver Side)

Once they found the codes, they backed down and immediately informed me that they would replace the servo motors and I should get the car back within the next couple days.

I'm just glad they found stored codes because I wasn't getting anywhere simply explaining my issue. If there weren't any codes, i have a feeling they would have turned me away. They gave me a ES loaner car and the air feels normal in it, so I know i'm not crazy (and i knew i wasn't crazy once other CL members here stated they had the same issue). Hopefully i'll report back with good news in a few days when i get the car back.

 

Thanks for update. I knew I wasn't the only one. Now the hard part is convincing them to hook up the diagnosti reader.
Was this still covered under warranty?

 

2016 IS350 here and i too have this issue. When aircon and fan is off it blows warm air.

If it's a common issue then based on your post could it be as simple as getting them to check for the error code with their computers? As you've experienced i would imagine it would be pretty difficult trying to convince them there's an issue.

 

Yes it should be covered under warranty. I am scheduled to get the car back this evening, so I will post an update at that time.

Yes my advice to other people is to try to get them to hook up their diagnostic computer and see if there are codes.


If there are no codes and you still suspect you have an issue, what I was thinking to do next would be to get an infrared thermometer (cheap from harbor freight) and do my own testing between 2 or more cars and measure the air temp coming out of the vents. Either try to have the dealer measure the air temp and compare it to another car on the lot, or do it yourself at home and bring them the results. That’s my plan in case replacing the servo motors doesn’t fix the issue for me (I think someone else posted in this thread saying servo motors didn’t fix it the first time around, so they had to replace the temp doors).

 

Picked up car update:

Received the car back last night and seems to be better. Will have to drive it around more to confirm. Hopefully it stays fixed!

 

1/23/19 update:
Passenger side is failing again. With both sides at LO temp on air from outside the passenger side is noticeably warmer than the driver side. I actually bought a harbor freight infrared temp gun so i'll measure the exact difference and post up.

I was afraid and pretty sure this would happen. I'm sure there is an issue with the part and Lexus probably just replaced my old faulty unit with a new unit that took at year to fail again. Only this time i think the car is out of warranty. I'll have to do more research and/or just replace the servo motors and hope it fixes it.

http://www.autocats.ws/manual/toyota...00stt00nx.html

 

Sorry to bump this up but going through the same issue. Passenger side will be hotter than driver side. Removed servo and even when holding door fully closed, its still hot on passenger side comparing to drivers side. What was your solution ? Thank you !!

 

Anyone have a diagram where they servo motors and blends are located? And how easily they are accessible?

 

What did the mice actually damage?

 

Here's an update for those that are still experiencing this like me. Per my last post, I decided to grab my temp gun and measure the differences in temp from one side to another. Before that, I took the passenger side under-dash area apart so I could visually confirm the servo motor was moving. Just like when you take your car into the dealer and the car starts working again, the servo motor wouldn't act up at all once I had it all disassembled. I left it like that for a couple weeks while my wife drove around with me sitting in the passenger seat adjusting the temp up fully up and fully down and it worked fine the entire time We decided to just leave it on full cold, that way the servo motor won't ever get the chance to stop in the hot position.

Anyhow, while i continued researching, i found this obscure youtube video that purportedly states the possible fix to this issue is just to reset the ECU (yes it says Remote Start, but the first thing he touches on in the video is the A/C problem and fix). Remove the neg terminal from the battery for 10 min, once 10 min has elapsed, turn the car to On pos 2 (do not turn engine on) to let the ecu initialize. Then hopefully the servo motor will be fully functional. I personally haven't tried this yet as my servo motors are currently working, but maybe someone else here can try it.

 

I dont think they damaged anything...just visually looking underneath the foot well. Can just see the **** and poop they left. Im sure if they bit into the wires a code would pop up or a warning but thats not the case.

Dealer thinks the warranty company wont accept the claim due the tracings of the rodent being in there. For them to fully diagnose they would have to take apart the dash which is around 13 hours of labor without fixing anything. Worst case i will file a claim with my insurance company.

 

Same thing happened to me when i got the car back from the dealer when they filled up freon. It worked like normal then after a couple of temperature changes it got stuck like it was set on HI.

I tried the battery reset and no luck. I read somewhere that a low battery can cause the AC/Air to not properly function. the dealer has warned me its time to replace my battery but the AC kicks on fine, car starts right up no issue.

 

the servo motors are located on the center tunnel under the dash. You basically need to remove the entire glovebox with the panels below it. IIRC, the adjacent panels to the right and left of the glove box need to be removed in order get the glove box out. These panel to the left of the glovebox is a triangular (i think) leather trimmed piece on the center console that just pops off and the panel to the right is the passenger side kick panel that covers some bolts on the right side of the glove box. It's all pretty easy, just be careful yanking on stuff because there's an airbag down under the glovebox. Any yellow loomed wires are airbag related and don't need to be touched for this.

 

Maybe try disconnecting your battery again, but for a longer period. Maybe 30 min or even overnight. If that still doesn't work, try to borrow someone's battery (if you're extra cheap ) or you could try charging up your battery with an external charger. If the battery actually is old, like 5-6+ years, then might be worth it to change it anyway.

I'm not going to pretend like i'm an electrical expert, but the fact that the youtube video guy's was fixed after the ECU reset and mine randomly works off and on, and the fact that there is no revised part from Lexus, makes me think the servo motors might not actually be the problem.

 

Haha that would be a good idea! But lets see I dont want to face this issue anymore because last thing the Servo motor to decide lets get stuck on LO or blow out cold air the middle of winter