My air conditioner in the vehicle works well when the car is running but in long idle the A/C light would start blinking and it will start blowing warm air. I went the a local shop they replace the AC condenser and the Freon with no success. Do you what would be causing my air conditioning system to still have that issue? Thank you!
Is the condenser cooling fan working?
If the condenser fans are turning on then you can try replacing the AC clutch relay. Your symptoms don't exactly match an issue with a faulty relay but you can buy aftermarkets for under $20, so why not try it?
You symptoms sound more like an issue with the Compressor Lock Sensor on the compressor. (sometimes called the compressor speed sensor)
Here's the circuit/system description:
Compressor Lock Sensor Circuit
SYSTEM DESCRIPTION
The ECM sends an engine speed signal to the A/C amplifier via CAN communication and BEAN communication.
The A/C amplifier reads the difference between compressor speed and engine speed. When the difference becomes too large, the A/C amplifier determines that the compressor locks, and turns the magnetic clutch off.
and it looks like this:
These days, these systems are unnecessarily complicated, but who am I to judge.
The idea behind it is if the compressor starts to fail and "locks up" the computer disengages the compressor clutch to prevent the serpentine belt from being shredded and disabling the vehicle.
In your case, find somebody with a high dollar scanner like Scotty uses.
This is going to be a code with a "B" prefix and a cheap scanner won't be able to retrieve those.
Something like, "B1422/22 Open or Short in compressor lock sensor", or some other "B" code referencing the lock sensor or compressor RPMs.
A slipping serpentine belt at low rpms could also cause the issue.
It could also be the wiring down there at the compressor.
So, get the codes pulled.
If it is the lock sensor you'll have some mechanics tell you that you can't buy a replacement sensor, you have to replace the compressor. That's not true.
But if you aren't a "Do It Yourself guy", you'll have to pay (in your case, again) to have the refrigerant evacuated.
Then they'll likely have to remove the compressor to replace the lock sensor.
Then the question becomes, does it make sense to pay for that labor and not replace the compressor on a 17 year old vehicle?
The answer: No it doesn't.
So again, get the codes pulled.
The lock sensor lives here on your compressor.
Yes, it does work but when the car idles for a long period it turns off.
That fan needs to be running whenever the AC is on, particularly at idle. You need an AC technician with a fancy scan tool that can do bidirectional testing of the electronics. Alternatively it would be possible to hotwire the AC system as Scotty has described in his videos if reluctant to put a lot of money into a car that's old enough to vote. (Might be enough to just hotwire the condenser fan in your case if that's the only problem.)
https://www.youtube.com/watch?v=0Foh6IF9Z5I