Need help with AC

Maintenance/Repairs
1

My car AC is weird in that sometimes it works and sometimes it doesnt. Sometimes I turn it off and back on then it picks up. Sometimes when I start the car it works perfect. But more recently it’s been getting warm and not cool at all. I have yet to gone through a full diagnosis. But my assumption is the compressor (based off a lot of youtube and google). Because just this April I took my car to a friends shop and he drained the freon and pumped more in. What steps should I take to diagnosis this problem?
My thinking of order of operation.
Check for any leakage (not sure how to do this)
Check the compressor (I assume try rotating the gear to see if its locked up)
Check the clutch. (Not sure with this one again)
And that’s all the checks I have. And yes I know to drain the freon and to suck out any moisture with a vacuum. Any can anyone check my work or any advice? Thanks!

Make: Toyota Model: Corolla LE
Working on my phone and it doesnt let me choose.

2

To check for leaks you use a refrigerant sniffer.

https://www.harborfreight.com/electronic-freon-and-halogen-leak-detector-92514.html

If the compressor is locked up it usually makes noise.

Run battery voltage to the compressor clutch electrical connector to see if the clutch engages.

That’s the basics for an AC system.

But each vehicle is different on how the AC system works. So, without knowing the year/make /model of the vehicle, not much advice can be provided.

Tester

3

I bought a tester. Sorry. I have to work off my phone and it wont let me put make or model. It’s a toyota corolla 2015 LE, it’s not making a noise or anything, so maybe a leak, I’ll have to see when the tester comes in.

4

What exactly is your a/c doing or not doing that makes you think there is an issue? This seems to be a lack of airflow and a blowing warm issue. Is it doing both?

Did your friend with the shop put enough refrigerant back in? How much did they take out? How much did they put back in?