[VW Beetle]

Hey,

when I bought my 2000 Beetle it was driving and nothing looked seriously wrong with it. It had a couple small coolant and vacuum leaks and other minor issues. I fixed all that and it really runs and performs well now.
The AC and the heat were not working. The heat blew only lukewarm air. Before the winter came, I followed this video. I took the dash partly apart to get to the blend door.

I taped the holes in the blend door and the heat is now blowing real nice hot air. After that was such a success, I want to fix the AC now for the next summer

When I press the AC switch, the light in the switch will come on. The fans will start turning, but the AC clutch will not engange.

I charged the AC system around half a year ago and replaced the AC pressure switch and this time.

I found this video and followed the instructions.

It is not easy to test the wires while the module is plugged in. I didn't do (2.) and didn't test the four pin connector. The fans are running so there should be power.
So far I progressed to number (8.) from the videos instructions. My results are:

1.9 V on pin 2.
12 V on pin 4.
pin 6 not tested yet
11.6 V to pin 8
11.8 V to pin 9
alternating voltage on pin 13, it changes quickly and I can see 4 V, 8V, 5 V on the display in rapid succession

The video tells me to verify approximately 70 % duty cycle on pin 2. What does that mean? Are 1.9 V 70 % duty cycle?

My willingness to lie further under the car and mess with those wires is gone for today and I will perform further tests tomorrow.

Maybe somebody has already some answers for my questions and maybe some further hints on how to get the AC running.

I performed above tests with the iginition on, but the engine not running - is that okay or does the engine have to run?

 

[VW Beetle]

I informed myself about duty cycle. The pressure switch seems to put out a frequency.

I put my multimeter into duty cycle mode and measured pin 2. Most of the time it showed 0 %. Sometimes after disconnecting the test wire and reconnecting it I could see different readings for a short time. The readings I saw were 10 %, 21 %, 70 % and 99 %. The duty cycle readings seemed very inconsistent to me.

The DC readings of 1.9 V with engine off and 2,2 V with engine on were stable. I also measured AC, that was stable as well at 4,8 V with engine off and 5,2 V with engine on.

I am using this multimeter

https://data.kleintools.com/sites/all/product_assets/documents/instructions/klein/MM400_1390110ART_WEB.pdf

Why don't I get a stable duty cycle reading?

I found the instructions from the video in text:

Tech Tip: Volkswagen Has No Power to the A/C Compressor Clutch

Click Here to Read MoreAdvertisement Vehicle Application: 2000 Beetle 2.0, 2002 Beetle 1.9, 2002 Golf 1.8, 1999-2003 Golf 2.0, 2000-’05 Jetta 1.8, 1.0, 1999-2005 Jetta 2.0 and 2000-’02 Jetta 2.8 Customer Concern: The A/C is not working. There is no power to the A/C compressor clutch and it does...

www.brakeandfrontend.com

I noticed that when the engine is on and the AC button is pressed the rpm will increase slightly every few seconds. It seems to me that the car wants to engage the AC compressor but can't.

I will do further testing tomorrow.

 

[VW Beetle]

I put 12 V to pin number 10 today. I didn't hear any noise. I also performed the test with the engine running and looked at the AC compressor. The clutch didn't engage.

I am going to test the clutch tomorrow directly.

 

[VW Beetle]

I applied direct power to the clutch today. Nothing happening!

I also measured the resistance between the two contacts - infinite resistance.

I need a new clutch. I think I could get one for 100 $ at one of the local auto parts stores. Or I can get one from the junk yard for 30 $.
I didn't see one at fcpeuro.

Can you recommend a good replacement clutch source?

 

[GreasySideDown]

Junk yard 100%. I rarely buy parts any more unless they're from a junkyard! It's really the proper thing to do to maintain the integrity of the Volkswagen brand.

 

[blu_koolaid]

Junk yard 100%. I rarely buy parts any more unless they're from a junkyard! It's really the proper thing to do to maintain the integrity of the Volkswagen brand.

Especially if you like doing jobs twice…


Sent from my iPhone using Tapatalk

 

[GreasySideDown]

Nah, gotta do the job at least 3x for it to be a real VW. Preferably with home made tools.

 

[VW Beetle]

today's yield from the trip to the junk yard:

When I disconnected the plug I noticed the tape on the wires. That meant probably that the compressor had been changed.

The initial plan was to pull the clutch but the compressor was from the outside in a good condition so I took the whole thing.
I measured the clutch' resistance: 4 ohm.

It is an Omega 20-01206-AM made in 2014. I pulled it out of a 1999 Beetle.

Now I will have to recharge the system but that's worth it to me for a 2014 compressor.

 

[GreasySideDown]

Chinese compressor, I do hope it works. Refilling the system is pretty simple. VW's are basic as they come with the A/C, shove some cans in it and call it good. My Subaru tech buddy recently tried to refill his B4 wagon the "proper" way with gauges and ounces and pressure etc and ended up overfilling it. When he turned it on it ran for a few moments then blew the pressure relief valve on the compressor. I told him the entire time to simply use the cheap 134a can refill method but he disagreed. After that experience he now agrees the cheap can method is the correct method.

 

[VW Beetle]

My trust in this compressor fades

I am draining the oil and this comes out.

When I turn the clutch a couple turns the compressor is locked. I assume this is not normal. Should an ac compressor always spin freely?

When I shake the compressor I hear some small parts in there. It sounds like metal debris
I think this compressor is gone. This junk yard offers a warranty and I can return it.

I will try to transfer the clutch. The chinese clutch should be compatible with the original compressor.

 

[VW Beetle]

I couldn't get the clutch off of this compressor so I returned it.

I bought a new clutch online. It was $50 and is called "FKG AC Compressor Clutch Kit". That is what I got:

The second retaining ring didn't fully fit into place. It is sitting in the groove but it didn't fully drop into it. To check I put the old clutch back on the compressor and the retaining ring is in the same not fully dropping in the groove position. I compared the thickness of the new parts with the old parts and they all match exactly. From my experience up to now I can recommened this product. It seems like a copy of the original clutch.

The air condition works now. So my problem was a faulty clutch.

Unfortunately I overtigthened the nut holding the clutch with my impact gun. The nut won't come off now but it is spinning. I will put some JB Weld on it to hold it into place. If the nut came loose the clutch would fall off but the pulley would stay in place. It is secured by the retaining ring.
For now this will be okay but I will get a new ac compressor in the near future. In any case I am happy I found out what the problem was.