A/C freon level

my AC for some reason stopped working the other day.  it works fine when i'm driving but whenever i slow down or am just idleing, it stops blowing cold air. i also noticed that my AC fan never comes on.  i'm assuming that its the same as mose cars, and that the AC fan comes on whenever you turn on the AC.  well mine never comes on.  i always thought it did because whenever i let the car idle with the AC on, i can hear a load being put on the engine and then taken off (like the sound of the fan coming on and off) but then i got out and watched the engine while it idled and the AC fan never came on.  so i'm assuming that it was my compressor turning on and off.  so i made a post asking why my compressor would turn on and off and i was told that if i was low on freon that it would turn on and off.  so my question is this....how do i check the level of my freon?  and where is the servicing port so i can fill it up if its low??

probably just low on freon, the compressor wont come on or go on and off if the freon pressure is too low.

yeah thats what everyone is telling me....but how do i check to see if its low?  and if it is low, where is the port to refill it?

there are guauges available at most stores, dont know if you ahve a battery cover bt its under that on the pass side, there are 2 a/c lines and you use the smaller one. its idiot proof since the gauge is designed only for the low side R-134a port.

great, thats what i needed to know, thanks
 

ok so i filled up the freon and it still didnt help anything.  my A/C fan still doesnt come on and its still not cold when at low rpm's.  it gets colder as i drive and the rpm's go up, but its still not nearly as cold as it used to be.  what could cause this?  could it just be that my fan isnt coming on and so therefore it isnt cooing off the condensor?   and thats why it gets colder at higher rpm's cause the wind is cooling the condensor.  does that make sense?  or what else could it be?

anybody??

If your low on Freon your compressor will NOT turn on until its properly filled.

Have you checked your fuses under the dash? You'll have to take the knee bolster off in order to see it.
There are some fuses there you should take a look at to see if thats where the problem lies.  I belive they were 40amp fuses and then theres 1    5amp fuse there

Looks something like this



 
 

i havent seen any fuse box like that in my car.  i looked at the litte fuse box located in the drivers side door jam on the side of the dash and none were blown.  i guess i can search for a fuse box looking like that one and see if any are blown.  it just doesnt make sense to me that it blows cold air when i'm driving at high speeds ( although not very cold still, but its still conditioned some though)  but maybe there is a fuse just for my fan and thats why its not coming on.   thanks, i'll keep looking

Hold your horses buddy, you're going about this all wrong.
1) Did you check for faults in the A/C control head using the VAG COM? If the ECON button stays lit all the time it means there is a major malfunction or you are out of R-134a.
2)Of course the air conditioner feels cooler when you're at high speeds, its getting air rammed into the condenser. If the fan isn't working then no air is moving through the condenser which means ITS ALWAYS GONNA BE HOT AIR IF YOUR NOT MOVING! Check for voltage at the fan after you check the faults.
3) Never, i mean never just throw in refrigerant if you don't know whats wrong with the A/C system, it almost never fixes the problem. Plus you don't know how much refrigerant to put in, overcharging the system is just as bad as undercharging it.
4) That fuse panel in the pic above is behind the panel under the steering wheel.....you have to take it off.
 
............ok im done ranting now.
 

From last summer my a/c wasn't as cold as it use to be. Now its just blows hot air and the compressor doesn't turn on. I'm guessing this means the freon leaked out. Right or wrong?

quote:

ORIGINAL: Trey25

From last summer my a/c wasn't as cold as it use to be. Now its just blows hot air and the compressor doesn't turn on. I'm guessing this means the freon leaked out. Right or wrong?

 
Ohi, its a good thing i have vodka in the system right now.
Just to clarify (for everyone) freon is the common name for R-12, not R-134a which is used on todays cars. I still have no idea why people call it freon since we haven't used freon since the 90's......
 
Anyways, if your losing refrigerant, the pressures would reflect that on both the high and low side. The system is sealed, so its NEVER supposed to leak. Re-charging the system will only cure the problem for about half the summer, depending on how bad the leak is.
 
Trey25: if the compressor stopped working there is a fault for it in the A/C control head which must be pulled out using the VAG COM. Only then can i tell you if its a refrigerant related concern, and not a compressor related concern.

yea but theres no lit econ button...well, I haven't noticed one. I'll just have get it on the VAG to see whats going on. Thanks though

Having a bad day yesterday? Rare I see you rant.

pete:  follow the steps on this link

http://www.audiworld.com/tech/int6.shtml

you'll be able to run a diagnostics on your a/c control system.

long story short. I utilized this method to determine that my high pressure valve was closed. which was an indication that I was low on R-134a which also lead me to believe I had a leak in the system. Which I did and I temporarily patched it up.

If you need help PM me.
Basically you will have to go through each of the codes and write down its results. I got some good help from Ewok over at audizine but he's in the process of moving so I dont think he's currently available.

One thing you can do is go to autozone or something and pick up one of those re-fill bottles with a gauge. Plug in the gauge to see if there's juice in the lines without re-filling.
You just want to initially check to see if you have any leaks.

ok i scanned my climate control using the link and the only system malfunction code i got was 22.3 (A/C refrigerant high pressure switch sporadic open)  anybody know the location of this switch?  but something else i found wierd though is i checked the RPM of the compressor and it said 56 when the car wasnt even on.  so then i turned it on and turned on the AC and checked it again and it still said 56.  so that tells me that the compressor isnt work right?  or could it be that the compressor is working and its just not sending the signal to the climate control. 

thats the same code that came up for me. Your compressor wont turn itself on because the high pressure switch is stuck. It is a safety feature with our compressors.
Which means that either your low on R-134 or you have a leak somewhere. Has the A/C ever worked?

With me, I filled up my a/c and two days later it emptied itself out. The day after that I purged whatever gas was left. Re-filled it with some gas ( I believe we filled up with 30psi of gas. ) In addition to that I used two bottles of leak fix which is a red dye. Eventually I found the leak coming from one of the pipes behind the radiator. So I used to epoxy to plug up the hole.

btw...to locate this switch you will have to remove your passenger headlight. once removed you'll see a a plug with 4 connectors.

I Doubt its the switch though.

ok, so i am losing R134a then.  yeah my AC used to work great.  i've owned the car for about 7 months and its been used many times and it always blew really cold air and then all of a sudden it stopped blowing cold air last week.   so i guess i need to buy a gauge and check to see how much is in the system and some leak check and do the same thing you did then.  i still have to figure out why my AC fan isnt coming on though

A/C fan will only come on when compressor is working.

Mine never came on until there was enough pressure to allow the compressor to turn on. So i suspect it gets triggered on when compressor is on.
What you should do is inspect whatever piping you can see with the hood open to elimate those.

Next step would be to jack up the car or a lift which would be easier.
Im sure the epoxy wont last long but, so far so good.

I agree with flyromero3, you're losing refrigerant. You can have someone inject dye into the system and use a black light to see where it is leaking from.
The most common leaks are close to the radiator, the connection at the firewall to the evaporator, and the evaporator itself. If the evaporator is leaking, your in for some serious repairs.

i bought an AC gauge and hooked it up and found that the compressor was kicking on and build pressure and then it would kick back off.  so then i started digging and found that my AC fan had a loose electrical connection and thats why it wasnt turning on.  so i plugged it in and fan came on.  then when the fan came on, the compressor stayed on instead of kicking on and off like before.  but because i put some R134a in at first cause everyone said it was probably low, i now have a little too much in the system.  its not into the red on the gauge or anything, but it is into the yellow part though.  but anyways, it all works again so i'm happy.  thanks for all the help 

I got code 22.1 Now I have to find where the hell its leaking from.

I believe the pressure in the low line has to be between 26-30psi

This seems to be the more common pipe that ends up cracking based on what my brothers friend told me that works at beiner audi.

If you have the car on the lift and are facing the front. When looking up you'll see two pipes. One of those pipes further up was what cracked on me.

It's not a simple thing to replace IMO, unless someone else knows how to. They do sell them on eBay but im not sure which one this is.