Check your radiator/condenser fan operation NOW

JBjunior

Veteran Member
Joined
Nov 27, 2007
Location
WA/NC
TDI
05 Passat Wagon/05 Passat Sedan/03 Jetta Wagon
I hate to start a new thread about my problem so I figure I will start here first. Here was the situation for my car (BTW I swapped from auto to manual a little while ago, and the AC did work for a while after the swap).
-AC stopped functioning suddenly, one day it worked the next it did nothing but blow warm air.
-Drivers fan wasn't turning on with AC button, replaced the fan, still didn't work.
-Compressor clutch still wasn't turning on with AC button so I replaced the clutch, still didn't engage the compressor.
-Figured the charge might be low so I had it evacuated and refilled, still didn't engage the compressor.
-Replaced the FCM, still didn't engage the compressor.
-Checked all fuses, none are blown.
-Took it to a garage to have them check it, they are saying that the AC button is not sending voltage to the FCM.
-WHERE DO I START LOOKING NOW?
A few hundred dollars ago the place to start would have been to actually troubleshoot, instead of throwing parts at it. At this point, the A/C button is a connection point to send power so it may be bad or a wire in between it and the FCM may be bad. Troubleshoot and see where you have power on the FCM and where you don't.
 

3turboz

Veteran Member
Joined
Jul 29, 2011
Location
Tempe AZ USA
TDI
2000 Golf GL Wolfsberg
Awesome, did a search because my fans were not working and found this thread. Followed the links and about 3 hours later I have both fans repaired (stuck brushes) and am back in business!

While the AC cut out initially made me check fan operation, I also had a couple instances where my 01M acted up. After pulling off the freeway on a long trip and into slow speed traffic, the tranny would have greatly delayed upshifts. Once I got moving again it would go back to normal. I'll bet that the non functioning fans are were playing a role there also as the trans temps were getting too high.
 
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spartan

Veteran Member
Joined
Aug 25, 2011
Location
MI
TDI
05 Passat Wagon
A few hundred dollars ago the place to start would have been to actually troubleshoot, instead of throwing parts at it. At this point, the A/C button is a connection point to send power so it may be bad or a wire in between it and the FCM may be bad. Troubleshoot and see where you have power on the FCM and where you don't.

I have done the trouble shooting hence why the parts were replaced, all were not functioning. I was just hoping someone had solved a similar issue previously. I will probably send it back to the shop on Monday as we are in the middle of getting a new garage constructed, so I have no where to work on it.
 

TheDieselIdea

Active member
Joined
Mar 17, 2010
Location
Spring Creek, Nv.
TDI
2003 Jetta
I have a question....On my 03 Jetta, at the thermo switch, I jump 1 and 2 and the low speed fans come on, but as per step 2, key on A/C button off, jumping 2 and 3 does nothing. When I jump it, it sends power on that wire to the fcm but nothing to the fans. Also no power to the compressor clutch at any time, all fuses are good. I can apply battery to fans and both speeds work fine. So, I'm thinking I have an fcm issue or a bad wire between the fcm and the fan. So I pull off the fcm and at the tabs base, the plastic is looking kinda burnt and the tabs are corroded. I clean it all up and get the tabs shining and still nothing. The burnt areas concerned me so I ordered one thru IDParts. Install new one and everything is still the same. Now I'm pretty convinced there is a wire issue between fcm and fan. Am I on the right track?
Backing up just a bit, One day my A/C is really cold, next day nothing but warm air. Turned key on, fan on and A/c button on and no cooling fans fans. The cooling fans were working a few weeks ago when I did this. I did notice that the last time the a/c worked, when I first turned it on, it was like the clutch was coming on and off really fast like a bad connection. I turned it off, waited a couple minutes and then turned it on and all was well. The next day nothing! Any suggestions would be greatly appreciated. Thanks in advance!!!
 

DanG144

Top Post Dawg
Joined
Aug 2, 2007
Location
Chapin, South Carolina, USA
TDI
2005 A4 Jetta 5spd
I would start with ensuring that you had good power flow available from the fuse box on top of the battery. Clean contacts down inside the box (have to unbolt all the lugs and take it apart), no signs of heating.

The operation you describe just before it died is symptomatic of actual or reported high pressure. If you had no cooling fans, then it is likely that you had actual high pressure. The actual high pressure can cause damage to the HP sensor, so you might want to check it out - it could now be reporting the wrong pressure. If you see oil around the electrical connector, then it is shot. The rapid cycling and high ambient temperatures can cause the clutch coil to burn up.

I would check the clutch coil resistance and probably try to jump power to it while the engine is running to see if it works.
 

RMoss

Active member
Joined
Nov 6, 2005
Location
VA, Centreville
TDI
PD Jetta, '04, red
I had my fan go out on my '04 PD and found this thread--really a great resource. Long story short: I got a new fan, but it had a manufacturing flaw and I put the original non-functioning fan in while awaiting a replacement. I read about Boeing Boeshield T-9 having good results with electrical/electronic equipment--it's a solvent, oil, and waxy protector when it dries--so sprayed a liberal amount in the old fan through the vent holes, let it dry, and spun it by hand before reinstalling it. It did not work initially, but lo and behold the a/c is blowing cold again and the fan seems to be working after a few days. The Boeshield might be worth a try. Hope this helps somebody else.
 

DanG144

Top Post Dawg
Joined
Aug 2, 2007
Location
Chapin, South Carolina, USA
TDI
2005 A4 Jetta 5spd
That T-9 dries to a waxy film. I would not use it in the fashion you did. I am glad you had good luck with it. I do use it on static contacts in bad (wet, salty air) environments (after cleaning the contacts), but not on brushes and the commutator.
 

RMoss

Active member
Joined
Nov 6, 2005
Location
VA, Centreville
TDI
PD Jetta, '04, red
Yeah, the T-9 leaves a waxy film. I figured I didn't have anything to lose by trying it since the fan wasn't working anyway. Lindsay VW in Sterling, VA said the fan wouldn't work even with a direct connection. They also wanted nearly $500 to replace the fan, so I was skeptical and thankfully checked here to see how easy it is. Anyhow, I spun the fan by hand and waited for the T-9 to dry (since it is flammable when wet) before reinstalling in the car to avoid hurting the electrical motor's internal parts. I have no idea if it's just a short term or a long term fix, so I'll report back. Fingers crossed in the interim.
 

79TA7.6

Veteran Member
Joined
May 8, 2006
Location
Live: Wilbur/Creston; Work: Moses Lake Washington
TDI
2003 TDI Jetta, 2002 TDI Golf, 2005 TDI Golf
I had a rock stuck between the pipe that runs from the passenger side of the condenser to the drier and rubbed a hole in the pipe. I had the hole repaired and today I got everything installed again. I have some cans of 134a and tried to fill the system. I know this is a terrible way to do so, but I did not want to spend a bunch of money for someone else to do it if the repair did not work. I was not able to fill the system at all. Car was running, AC on high, and hooked up to the low pressure/suction line. The compressor will not kick back in. I am not sure what to do. I am assuming that having a can of refrigerant hooked up that I would get enough pressure to eventually kick the compressor on, but this is not happening. I have read through the documents in the first post but none state how to fill an empty system, to go to the professionals. I really do not want to do that just yet.

Please help.

EDIT: And I do have 9.5 volts at the plug on the compressor. and 4 ohms at the clutch. AC was working perfect before I lost pressure because of the rock.
 
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martins23

Member
Joined
Jan 27, 2011
Location
Latvia
TDI
BORA PD150 variant
had a problem with my fans also. Changed fcm and they started to work, but without first speed, only second when ac turned on. And now my new fcm burned again, what could couse that problem? Stealer sead, that coud be the fans, too much load giving to fcm
 

SoKYTDi

Veteran Member
Joined
Feb 28, 2007
Location
Franklin, KY
TDI
2003 Golf GL 4-door
I had a rock stuck between the pipe that runs from the passenger side of the condenser to the drier and rubbed a hole in the pipe. I had the hole repaired and today I got everything installed again. I have some cans of 134a and tried to fill the system. I know this is a terrible way to do so, but I did not want to spend a bunch of money for someone else to do it if the repair did not work. I was not able to fill the system at all. Car was running, AC on high, and hooked up to the low pressure/suction line. The compressor will not kick back in. I am not sure what to do. I am assuming that having a can of refrigerant hooked up that I would get enough pressure to eventually kick the compressor on, but this is not happening. I have read through the documents in the first post but none state how to fill an empty system, to go to the professionals. I really do not want to do that just yet.

Please help.

EDIT: And I do have 9.5 volts at the plug on the compressor. and 4 ohms at the clutch. AC was working perfect before I lost pressure because of the rock.
Okay, did you also AT LEAST have the system evacuated? Do you have oil to put back into the system? Without someone pulling the vacuum on the system (evacuation), you will likely not be able to get anything back in the system and have it run for long. Even with a small hole, there is moisture in your system now, and possibly some other contamination. You might even look at replacing the orifice valve as well, since it will collect any crap that got into your system. If I'm out of line, I'd expect someone will set me straight.

I'm no A/C expert, but I did work in the aftermarket parts industry long enough to get certified to work on them. Had I the money for the equipment at the time, that is likely what I would be doing now.
 

DanG144

Top Post Dawg
Joined
Aug 2, 2007
Location
Chapin, South Carolina, USA
TDI
2005 A4 Jetta 5spd
Play around with the fittings on the low side. It sounds to me as if your cheapo fill unit is not actuating the schrader valve to allow flow.

I agree that replacing the drier, adding a bit of oil to replace what was lost with your charge, and evacuating the system would be smart.

What you are trying to do for a simple test should work (though I would use a manifold and gauge set).

If you run the system with moisture and air in it, it will not run well or last long.

I had a rock stuck between the pipe that runs from the passenger side of the condenser to the drier and rubbed a hole in the pipe. I had the hole repaired and today I got everything installed again. I have some cans of 134a and tried to fill the system. I know this is a terrible way to do so, but I did not want to spend a bunch of money for someone else to do it if the repair did not work. I was not able to fill the system at all. Car was running, AC on high, and hooked up to the low pressure/suction line. The compressor will not kick back in. I am not sure what to do. I am assuming that having a can of refrigerant hooked up that I would get enough pressure to eventually kick the compressor on, but this is not happening. I have read through the documents in the first post but none state how to fill an empty system, to go to the professionals. I really do not want to do that just yet.

Please help.

EDIT: And I do have 9.5 volts at the plug on the compressor. and 4 ohms at the clutch. AC was working perfect before I lost pressure because of the rock.
 

wmgeorge

Veteran Member
Joined
Jun 22, 2012
Location
Central Iowa
TDI
2000 New Beetle GLS 1.9L TDI
I have a question....On my 03 Jetta, So I pull off the fcm and at the tabs base, the plastic is looking kinda burnt and the tabs are corroded. I clean it all up and get the tabs shining and still nothing. The burnt areas concerned me so I ordered one thru IDParts. Install new one and everything is still the same. Now I'm pretty convinced there is a wire issue between fcm and fan. Am I on the right track?
and all was well. The next day nothing! Any suggestions would be greatly appreciated. Thanks in advance!!!
If you have a bad connection and it burns the other side, chances are that is bad also. I don't see how a wire could be bad I'd suspect the connections. Fans are working with direct connections and you get power to the FCM, I'd replace it first.
 

79TA7.6

Veteran Member
Joined
May 8, 2006
Location
Live: Wilbur/Creston; Work: Moses Lake Washington
TDI
2003 TDI Jetta, 2002 TDI Golf, 2005 TDI Golf
Play around with the fittings on the low side. It sounds to me as if your cheapo fill unit is not actuating the schrader valve to allow flow.

I agree that replacing the drier, adding a bit of oil to replace what was lost with your charge, and evacuating the system would be smart.

What you are trying to do for a simple test should work (though I would use a manifold and gauge set).

If you run the system with moisture and air in it, it will not run well or last long.
So the cheapo can and charge fitting I have should be able to put in enough pressure to the system to at least get the compressor to kick in? If I am able to get the fitting to fit better and still cannot get it to draw any fluid in I might have another issue now? I understand the need to totally evacuate the system, but I was hoping to be able to test it out first. It looks like I might be going to an AC place to get their take on this ordeal too. Thanks for all of the help guys. This is hard for someone like myself to do as I have always been my own mechanic since my first truck. This AC trouble shooting is for the birds, unless of course you know how to do it. :rolleyes:
 

Lightflyer1

Top Post Dawg
Joined
Sep 13, 2005
Location
Round Rock, Texas
TDI
2015 Beetle tdi dsg
It is no different than anything else, except for the part dealing with vacuum and freon. With all the rules now if you don't have the equipment to remove and recycle the freon you will be in trouble in short order. In the old days you could get by with a vacuum pump and manifold set. Most now days cannot afford the freon machine for an occasional use.
 

Jettadoor

Veteran Member
Joined
Jul 2, 2009
Location
Neuville P.Q. Canada
TDI
2000 Auto 419,000Km. +/-(260,000miles)
I changed a bad fan, FCM and compressor coil and after having the system checked out at a local shop the pressures are spot on, no leaks, all is fine. I would never have undertaken this work without all the information I found here and my AC would not be working at the moment. Thank you everyone!

My issue at the moment is with the operating temperature of my new driver's side fan, a Valeo. The first couple of times I plugged it in a bit of smoke came out; although the smoking has diminished it runs quite a bit hotter than the smaller fan. I pulled the old fan to bits and the plastic brush holder was completely melted. I have checked my ground from the fan connector and I have .2 ohms, same as the T14-6 connector.

My feeling is that my new fan will be toast in the not too distant future so I have been looking for a fix. I followed a link posted elsewhere by DanG to a british forum where I found details on a resistor circuit mounted on a heat sink.

http://website.lineone.net/~alan.james.lorely/fan%20mod/Repair.html

This mod replaces the low speed circuit in the motor with a 1 ohm 100W resistor mounted on a heat sink and T'd from the low speed 12V wire into the hi speed wire after cutting the low speed wire. If you follow the link and look at the photos the resistors seem to be bullet proof.

Has anybody seen this mod or tried it out? It seems the driver's side fan is particularly problematic and I may try it out on that one because I don't think it will last all that long. An old fuel cooler could make a good heat sink.
 

wmgeorge

Veteran Member
Joined
Jun 22, 2012
Location
Central Iowa
TDI
2000 New Beetle GLS 1.9L TDI
My issue at the moment is with the operating temperature of my new driver's side fan, a Valeo. The first couple of times I plugged it in a bit of smoke came out; although the smoking has diminished it runs quite a bit hotter than the smaller fan. I pulled the old fan to bits and the plastic brush holder was completely melted. I have checked my ground from the fan connector and I have .2 ohms, same as the T14-6 connector.

Neither one of my new Dorman fans (Made in Thailand) smoked when I installed or since. I'd contact the people you purchased from and get a replacement on the way.

Yes I agree with you, we have a great resource here on the TDI Club... the People.
 

Jettadoor

Veteran Member
Joined
Jul 2, 2009
Location
Neuville P.Q. Canada
TDI
2000 Auto 419,000Km. +/-(260,000miles)
My issue at the moment is with the operating temperature of my new driver's side fan, a Valeo. The first couple of times I plugged it in a bit of smoke came out; although the smoking has diminished it runs quite a bit hotter than the smaller fan. I pulled the old fan to bits and the plastic brush holder was completely melted. I have checked my ground from the fan connector and I have .2 ohms, same as the T14-6 connector.

Neither one of my new Dorman fans (Made in Thailand) smoked when I installed or since. I'd contact the people you purchased from and get a replacement on the way.

Yes I agree with you, we have a great resource here on the TDI Club... the People.
I take your point but the Valeo was the best fan i could get. There are cheaper fans out there! The Dormans that I saw were in a paired assembly and my other fan is OK. I do not believe in scrimping on parts and will always pay more for better quality when it is available but I don't like replacing parts that work. I interpreted the initial smoking as being nothing more than you would get out of a new toaster or toaster oven and my estimations of temperature are literally "hands on, seat of the fingertips". The passenger side fan gets hot too, but did not burn out.

It's just that every other post I read over the past few days talked about a bad driver's side fan and rarely do they mention what make fan it was. Maybe not everyone notices that their new fans are running hot.

I have also read on the forum that the ideal fan does not exist; brush systems and their mounting plates and especially the resistors seem to be the issues. The coil wound aluminum clad resistors in the mod are bullet-proof and take most of the heat out of the motor housing. I think this will improve the life expectancy of the rest of the motor components.

I have just been sourcing the parts for this mod and they cost less than the shipping and re-stocking charges for my new fan so I will be going ahead with it. It may take a few days to get all the parts together and installed but I will do it and let you know how it goes, results wise.

Yes, the people are the best resource on this forum and I am seriously mulling over the possibility of making it to the TDI FEST near Detroit to meet me a few of them! As an ex-patriat Brit living in Québec, recently retired, I have long been thinking of making a dash into Ontario to get some good fish and chips; now, if I go another tank-full further I would be in Detroit. Any good fish and chip shops in Detroit?? :)
 

wmgeorge

Veteran Member
Joined
Jun 22, 2012
Location
Central Iowa
TDI
2000 New Beetle GLS 1.9L TDI
I put the Dorman's on because I needed both fans and it seemed like everyone was selling the exact same ones. The prices varied from what I paid $97 for the pair to nearly $260 for the same model and part number. I saved my old OEM fans and some day when I get bored I will take them apart to see how and where they failed. I am a electrician among other skills, learned in the US Air Force.... air craft electrician.

I kind of suspect the dropping resistor for the slow speed is the failure point and you are on the right track with the modification. Not sure where you are getting the parts from??
 

seaglf

Veteran Member
Joined
Feb 21, 2010
Location
Houston Texas
TDI
2002 Golf GLS Automatic
Mod

I just got back from a test drive of my car after a mod. that I have done...Now don't think I'm exaggerating or that I'm imagining this, but I have a complete transformation of my car. As soon as I started, it I could tell that it sounded different, it was Idiling more smothly and sounded quiter,(suspected the timing was off and maybe giving to much fuel). It accelerated more quickly and shifted earlier. NO Joke! the brakes seem to work better,(suspect the ABS system is working better).

Most noticable difference is that the AC blew Instant freezing cold air,(must be because of the fan circut).

Another thing I noticed was that I had been getting crossed Temp readings on my scangauge When set on Water temp I would get quik flashes of temp from tranny, confirmed when I would set it to tranny temp, and I could never get tranny and water temp at same time. Now I can get both.(assume it has to do with the ECU).

OK here is what I did, The part from ECS tunning was wrong so I am sending it back for new one. Meanwhile I decided to open the back of my Fuse box and take a look. Well there wasn't any obviuos burns from the outside,except for the 30amp fuse. But inside you could see that the 150 amp plate fuse had been over heated a little. Figuring that there had been to much resistance from the main cable,the red one that goes from the battery to the fuase box,(and it looked like it had gotten a little hot before). I decided to replace that cable with the next larger size 4 gauge, and used the copper terminals they sold for it at Orielly's. I cleaned all the surfaces with emory board an then put it back together.

Now I am not one to exagerate but it just seems like everything is working better. I believe that free'r flow of electrons has helped alot.
Now this is just an expeirment and I don't intend to leave it that way unless it really makes a differnece. In any case I do intend to replace the altenator harness. And I am going to watch and see if the Code P0128 comes on my scan gauge again. Also I am going to take it on a long trip to check my mileage.

One other question, would it make a difference if I replaced the main alternator cable with the next larger size, or does having to little resistance effect the system
 
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seaglf

Veteran Member
Joined
Feb 21, 2010
Location
Houston Texas
TDI
2002 Golf GLS Automatic
OK took it for another drive today and the P0128 code came on again. Although everything else seems to still be working better including the AC. Usually when I get that code the AC starts putting out warmer air, and/or makes that medium frequency whistling sound in the lines.

does that code also have to do with the fan Circuit or is it just with the coolant part of the system. I have replaced both the Thermo. and the Coolant sensor ( Green one)
 

wmgeorge

Veteran Member
Joined
Jun 22, 2012
Location
Central Iowa
TDI
2000 New Beetle GLS 1.9L TDI
OK took it for another drive today and the P0128 code came on again. Although everything else seems to still be working better including the AC. Usually when I get that code the AC starts putting out warmer air, and/or makes that medium frequency whistling sound in the lines.

does that code also have to do with the fan Circuit or is it just with the coolant part of the system. I have replaced both the Thermo. and the Coolant sensor ( Green one)
Did you find this to read? > http://forums.tdiclub.com/showthread.php?t=322940
 

DanG144

Top Post Dawg
Joined
Aug 2, 2007
Location
Chapin, South Carolina, USA
TDI
2005 A4 Jetta 5spd
If you have not already cleaned the grounds for the engine, battery, body and ECU, I would to so. (So the large and small grounding posts (2 small?) under the battery box, big ground on the transmission, small grounds for the ECU (and maybe auto trans) in the windshield plenum.

Clean them, don't just look at them. Do a wiggle test and ensure the crimped lugs are good.
 

seaglf

Veteran Member
Joined
Feb 21, 2010
Location
Houston Texas
TDI
2002 Golf GLS Automatic
If you have not already cleaned the grounds for the engine, battery, body and ECU, I would to so. (So the large and small grounding posts (2 small?) under the battery box, big ground on the transmission, small grounds for the ECU (and maybe auto trans) in the windshield plenum.

Clean them, don't just look at them. Do a wiggle test and ensure the crimped lugs are good.
I will check all that, as well as replacing the alternator harness. All my problems started a few years ago after I ran over a curb. It bent the drivers side suspension arm which they replaced, as well as breaking the oil pan, and I could see where it hit the tranny plate. So maybe some of the grounds are lose.

I should have had all this done a couple years ago, but I haven't been in the position to work on my car much.
 

79TA7.6

Veteran Member
Joined
May 8, 2006
Location
Live: Wilbur/Creston; Work: Moses Lake Washington
TDI
2003 TDI Jetta, 2002 TDI Golf, 2005 TDI Golf
I have not had the money to get my AC refilled after replacing the condenser, but I was thinking about it a lot lately. If I have no charge on the system at all and I push the AC button, will my fans turn on? They currently do not, but I was thinking I read that they would. If they are supposed to turn on then I have another issue I need to resolve before taking it to the AC repair shop.
 

kd7iwp

Veteran Member
Joined
Jun 27, 2009
Location
Abbotsford, BC, Canada
TDI
2002 Golf GLS
Thanks to the OP for this thread. My large driver side fan hasn't been working so I followed the PDF to the T and had the same problem where my brushes would no longer slide smoothly and weren't touching the commutator anymore. After doing all this it works perfectly, better than the other fan even. Thanks!
 
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