Automotive Air Conditioning Information Forum

That’s a tough one… and honestly, you’ve already gone way deeper into it than most people would.
At this point, it really doesn’t feel like the HVAC module itself - 4 replacements all doing the same thing is a big clue. Feels more like something making the module lose its mind.
The way it switches ...

That’s a tricky one, especially since you’ve already done a lot of the right things.
From what you’re describing, it honestly sounds like the cooling system is just right on the edge, and the AC is pushing it over when it’s hot out. 200°F isn’t crazy, but with AC + 85°F ambient, it adds up fast.
One ...

Hey, you’ve done a great job piecing this together — your logic is actually pretty sound.

What you're describing does sound like it could be related to either overcharging or a cooling fan issue, possibly even both. When an A/C system is overcharged, it can definitely build excessive pressure ...

Yes, it could definitely be a leaky O-ring. O-rings can dry out, crack, or lose their seal over time, especially on older cars like a 2011. That spot where the high-side line meets the condenser is a pretty common place for O-ring failures.

That said, your mechanic might suspect the condenser ...

Absolutely agree, Tim!

Using proper gauges is essential when working on auto AC repairs. It's the only way to accurately measure both low and high-side pressures, which are crucial for diagnosing and fixing AC issues effectively. Investing in the right tools not only ensures safety but also helps ...