A/C problem - help needed.

[hunds02]

Originally Posted by Zulu95

The AUX fan in SOP will run for as much as minutes after the vehicle is shut off. Some people throw out FSR/FSU as the reason for every AC woe. It's like an automatic reaction.
The TOTAL charge for the system is just under 1 can from all accounts. If you need to recharged then you must have a leak. I had to replace the Service Port (High & Low) seals some years ago. The OEM seals were revised and a kit issued for older models so that standard "O -rings" can be fitted from then on. Cost was $11 per port or so then.
I took it to an AC repair shop. They found the leak and installed the new seals that I supplied, vacuumed out the system and recharged everything with the proper amount of "freon and oil for $95. Worth it when you consider the price of other parts should the recharge be done wrong!

Well to be honest I don't know if it needs to be recharged, all I know is the aux fan is not coming on, and that I have cold air on the driver side. I may indeed have proper freon pressure. If it is true that low freon levels will cause the aux fan to shut off then it is probably low, but that doesn't mean I have a leak right? Freon was never added to the car since it was bought brand new in 2005.

[TiAgX5]

Originally Posted by hunds02

My pressure level was 45 psi, but the aux fan is off so the pressure would read higher. So how do I know how much to add? I do not want to overcharge it. Is one can too much?

45 psi is fine if checked in an ambient temp of over 90deg F (the low pressure side reading will drop/rise with temp change). The system only holds around 14oz of R134a and 2oz of compressor oil, DO NOT ADD EVEN A SMALL (12oz) CAN! If you add do it in small (1 or 2 oz) increments.

[hunds02]

Originally Posted by TiAgX5

45 psi is fine if checked in an ambient temp of over 90deg F (the low pressure side reading will drop/rise with temp change). The system only holds around 14oz of R134a and 2oz of compressor oil, DO NOT ADD EVEN A SMALL (12oz) CAN! If you add do it in small (1 or 2 oz) increments.

I understand this, which is why I didn't add any and immediately disconnected the can. But I feel like no one is addressing my main issue. That issue is that these pressure readings are not reliable if the aux fan is off, I don't know by how much but I need to know. Maybe I really have like 25 psi, I will never know what the actual pressure is since the aux fan is not coming off.

[hunds02]

Originally Posted by hunds02

I understand this, which is why I didn't add any and immediately disconnected the can. But I feel like no one is addressing my main issue. That issue is that these pressure readings are not reliable if the aux fan is off, I don't know by how much but I need to know. Maybe I really have like 25 psi, I will never know what the actual pressure is since the aux fan is not coming off.

last line is supposed to read :"since the aux fan is not coming ON"

[TiAgX5]

Originally Posted by hunds02

I understand this, which is why I didn't add any and immediately disconnected the can. But I feel like no one is addressing my main issue. That issue is that these pressure readings are not reliable if the aux fan is off, I don't know by how much but I need to know. Maybe I really have like 25 psi, I will never know what the actual pressure is since the aux fan is not coming off.

You need to back probe the electrical connector on the aux fan to see if there is voltage. If the reading is OK, the fan will need to be replaced.

[Zulu95]

Did you test the AUX fan and/or the AUX fan relay to see if it either is faulty?

[hunds02]

No not yet, I am at work but thanks for the suggestions, I will test the aux fan first thing when I get home

[hunds02]

Anyone know where the aux fan relay may be?

[hunds02]

I tried to pull the plug on the pressure switch on the lower AC line, however the fan still did not kick on. Is this the pressure switch I should be checking?



I will check the voltage on the aux fan later.