superkurt

Just curious, did you ever get this fixed or is it still an issue? We are having the same exact issue with our 2016 RX 350. It only happens when we are a few hours into a long trip when it's super hot outside. This last time we were actually able to get it to a dealership as the issue was happening and they still couldn't find the problem.

RollingBlu

The Ac hasn't failed but it hasn't had to work hard either. So, no, it hasn't been fixed.

pnv5001

Hey guys! I came upon this forum and thought I should share my experience with you. I had this happen on my Lexus NX 200T 2015 model 3 years in from having it. I live in Puerto Rico where the weather is hot all year long, and to make matters worse, my Lexus is all black (exterior and interiors)! Anyways, I had the same problem where when the day was extremely hot, I would turn on the car and the AC would not turn on, period. What I noticed was that as a I drove for a while with the windows down, the A/C system did turn on. Another thing I noticed (very important), was that the outside temperature read "E" on the dash. No fahrenheit reading was recorded, and once I drove for a bit it would start reading the temperature and only then will the A/C system start again. I took the car to the dealer as it was still under warranty and I can't remember right now exactly what was replaced (I will look at the service papers, it was something with the electronics definitely) and the problem was fixed.

Also, just yesterday I set my a/c on a warmer setting and it automatically started throwing really hot air! I couldn't get it to throw cold air no matter what I did (put the coldest temperature, pressed the dual buttons to see if it was only one side and nothing, turned the car off and turned it back on, etc.). After researching a little on google, I found that this is somewhat of a common problem and that it has to do with the "hot/cold air mix servo". I went to the dealer this morning (but this time no warranty) and they said these servos have been failing in the newer Lexus models and that the replacement and installation is around $1,200!!!! Of course I was not about to pay that, so I told them to connect the OBD2 scanner and try resetting the system. They then told me after connecting the OBD2 that they got 3 alarms, one alarm was for low battery and the other two were two of the air servos (aha!). I asked for them to reset the servo setting, but they told me they would have to replace the battery in order to do that (which I agreed to), and thankfully, it worked. So I didn't have to look for a family mechanic and order these servos, wait for them to get to Puerto Rico and replace them!

Hope this information helps!