I have a 2011 3rd gen rx 350, my AC mode button doesn't seem to be do anything. and the AC resets to 75 when the car is started, it takes about a minute for it become responsive and then I can make an adjustment to temps and fan speed. I tested heating and AC cooling still works but the "Mode" button doesn't seem to do anything. I can't switch between lower and upper air vent. I took it to a dealer and they want $2500 (parts and labor) to replace servo motor and the air vent assembly. that is an absurd amount of money to fix the "Mode" button. worst case scenario I could just live with the "Mode" stuck on it current position (mixed even split between lower and upper vents).

Any help with picture or instruction for locating and replacing the "mode" servo will be great. thanks.

 

I believe that thing is buried up the AC/heater box assembly.
Maybe not even visible to check.
Meaning the whole thing has to come out to access it.

 

 

 

 

Update 1/9/2019.REALLY GOOD NEWS !!

Lexus Guest Experience gave me a call directly today with some really good news!!
My dealer service consultant reached out to Lexus for out of warranty assistance (the same time when I sent email to Lexus about the same issue) and Lexus HQ decided to cover the all parts and labor for my the failed servo replacement as a one-time goodwill gesture as part of Lexus' unmatched customer service. They have been providing 8 years of great customer service and now they just took it to the next level.

 

Booyahhh...!!!
Time for a cold one.