[Benjamin]

Not the S Model – The symptoms are: no cold air and little electrical anomalies like erratic engine idle, or high engine idle, or an occasional sputter.

I tested both cooling fans, all okay. A mechanic tested my 1-year old Behr compressor, he says it is working. He also tested the Freon, that checked out satisfactorily. I pulled the 3 fuses out several times and reseated them (I assume this area is okay, but cannot prove it). Any thoughts?

 

[300exoh]

Try cleaning the contacts on the fuses. Emery cloth, fine sandpaper or even steel wool will work. The slightest bit of corrosion will cause similar symptoms. Check for corrosion in the contacts in the fuse block as well.

 

[pencilneck]

This might be helpful:

 

[Benjamin]

Thanks for the reply! Okay, I pulled the 3 fuses out cleaned them with 320# and reseated them; also, I cleaned (the best I could) the contacts wherein those fuses seat. When I “fiddle” with these fuses (with the engine running and the AC on) I hear the idle fluctuate, and I hear a faint clicking from the compressor area but cannot say exactly where the sound originates. Any thoughts?

 

[Benjamin]

Thanks for that Sensor chart (not that I completely understand it). Rather than expensive diagnostics, I'm inclined to just change a part, on spec, and see if the problem goes away. Given the auto's symptoms, my question is: what sensor is most likely preventing a steady current to the compressor? Yeah, I think that's what I mean

 

[billymade]

Sounds like you may have the dreaded melted fuse box on top of the battery; it can cause the a/c compressor to not come on or intermittently come on/off, because of poor contacts with the fuses. My Beetle seemed to have a mind of its own; even with the a/c button depressed, it would go on, off, at will and sometimes not at all. As a temporary fix; I cleaned/bent the connection tabs and fuse to have a better connection. For a permanent fix; I ended up replacing the fuse box on top of the battery.

Check out this link for more info; the "clicking" sound is the a/c compressor coming on and idle will be affected by the extra load of the compressor clutch engaged.

No Compressor Operation in Volkswagen New Beetle

No Compressor Operation in Volkswagen New Beetle

 

[Benjamin]

Well, I used an emory board to scuff the contacts in the slots where the fuses seat, but no changes. Now I don't know if this means I did a poor job, or if it's something else. Could a fuse(s) be broken in an area (invisible to the eye)?

 

[ggoat!!!]

I have had the same problem; I have recently found the cause and it's not fun.

My A/C has been out for a LONG time now...same conditions as you, compressor working, fans good, full of freon, no leaks, all electrical connections are fine and working just no cold air. Mine USED to get cold at a stop then the second you would drive it would stop blowing cold.

My problem turned out to be the desicant in the dryer broke free and completely and totally clogged the high pressure line between the dryer and the expansion valve (and the valve itself). When I say clogged I mean C-L-O-G-G-E-D. I have a new dryer and expansion valve, but I haven't found a shop that can clear the line. The line is nearly $400 from VW. I am determined to get the desicant out of it but can't see how...it has numerous tight bends. It also looks like a major b*tch to change. I have put nearly 200psi on the line and it doesn't budge. The entire contents of the dryer are impacted in the line. The only good thing is that the desicant didn't make it past the expansion valve nor did it backflow to the compressor.

I used to leave mine on all the time hoping it would "kick in" and work as it did when I would come to a stop, but all I was doing was packing and packing and packing and packing the desicant harder and harder into that damn line.

But, my A/C still doesn't work...and no shop I've been to can give me an idea how to get the crap out of the line.

This sounds like the same thing yours is doing.

If you figure out what it is or that you are clogged with desicant and you get it out, please let me know how you did it.

Jeff

 

[Benjamin]

Wow Jeff, sounds like you (and maybe me) have an endurance test waiting for us. Just don't know what to have tested, and in what order..... If I learn anything, I'll let ya' know - Thanks, Benjamin

 

[pencilneck]

Several different factors can cause the AC to not work. The most common is the failed fuse block on top of the battery, and that is the easiest to resolve. You mention that you've pulled the fuses out several times, I'm guessing you checked for signs of melted plastic when doing so.

Blindly tossing parts is not the smart way to fix the car. Lets use our grey matter and try to narrow this down some.

With the engine cold, start engine and let idle. Turn on AC, the AC button on the dash should light up yellow. Now check your coolant fans.

Are the coolant fans running?
Is the clutch on the A/C compressor engaged?

Shut engine off, turn ignition on. Unplug the High Pressure Sensor. Check for voltage from T3c/3 to ground.

What is the voltage reading?
Is there oil leaking through the High Pressure Switch (it should be clean and dry when you unplug it)?

Locate the 14 pin connector on the Fan Control Module, unplug it. Ohm test from terminal T14/10 to ground.

What is the Ohm reading?

Use a hook pick, gently tug on each of the wires at the 14 PIN connector, sometimes they rot apart inside and will pop right out when you tug on them.

He also tested the Freon, that checked out satisfactorily

This is a VERY open ended statement to me. I deal way to often with people who tell me that the AC has freon... but then can't answer a simple question....

How many grams of freon is in the system?

 

[Benjamin]

Chronological replies to Pencilneck:
1 - Fuse block & fuses - I wouldn't know how to check if the fuse block failed, but no fuses were melted or blown
2 - Gray matter - yes, here I have a few leaks (unstoppable, I might add - oddly enough, I have a background in theoretical physics, but cannot fix a car)
3 - Yellow AC light comes on and AC fans come on when AC button is depressed
4 - I am told that the clutch is intermittently engaging (or trying to engage) and then instantly disengaging
5 - As for voltages and impedance, I cannot comment as I have no test equipment
6 - As for the Freon, I don't believe he tested the gram weight. But I have to ask, will improper amounts of Freon mask itself into an issue that appears electrical? Just wondering...

Thanks for your reply!