As many of you know, I am a professional tech, ASE Master Certified since 1979, L1 since its inception whenever that was.
My wife's 2010 I4 AWD RAV4 base has been having AC issues. Driving along, or sitting at a stop light, the air coming out of the vents gets noticeably warmer. Then it will cool great for a while, then it will get warm. Some days it is great. A few days my wife said it took longer than usual to get cool air coming from the vents after startup. I have experienced this myself, so it's not her.
Toyota has a bulletin about a faulty flow sensor in the compressor, but the VIN falls outside of what Toyota says is affected (by a lot).
If this were any other Toyota product with a relay, I would suspect the MG CLT (AC clutch) relay but this does not use a relay.
We went on vacation over the labor day holiday, and my wife drove about 3 1/2 hours. I had the laptop connected running Techstream, monitoring the flow sensor, evaporator fin thermistor, pressure sensor and something else.
Naturally, it worked great all the way down. We were leaving to get some supper and the AC was blowing warm air. I didn't have anything connected (naturally) so I could only slap my forehead.
I drove the 3 1/2 hour trip back, and didn't want to have my wife bothered by the laptop and all the cables, but it worked fine all the way back.
No fault codes are stored, and when it cools it cools great.
I am SO glad this is not a customer's vehicle. They would think I don't know what I am doing.
After being married to me for 35 years, my wife knows that some vehicles I work on are possessed and they know when a professional tech is trying to figure it out.
That is why my personal car never breaks down. :laugh