This was such a great video man! Love how you showed your son step by step and mostly me as a viewer. Some people don't even do that. I appreciate this video so much! Great job and thank you!
So good to see your son working with dad ...your so good with him passing on your knowledge and he asks some great questions aswell great video helped me out a lot👍👍👍👍
He said awesome when the fan came on when he touched that connection. He will remember that forever. That’s so good to get your young kids out to do this stuff. He might become an electrical engineer now.
Great test and teaching your son . I just mentioned your advice on testing a fuse on my ac and fan on my tdi jetta . I changed out the module I had a spare and no clue how this system lol and that did not fix it . It was a fuse on top of battery that would light up a test light but it had the crusty on the blades of fuse . Cleaned the blades and sure enough the fans worked ac came on . So after that I thought well Paul said under a load while I drank a cold beer . Lesson learned thanks for all you do
Well done- this is thumbs up for Mr. Beau Danner - hope to see you again helping your dad and asking lots of questions so you can learn just like we all do. Great Job Beau
Say man ur one hell of a teacher/instructor/ guide etc. Love the way ur level headed enuff to stay connected to Beau and to answer him correctly. And Beau is on point as can be he was recording ur every word which was why he thought ur statement was contradictory about whether hot was good or bad. Great question good answer. Really appreciated this video this morning..
I'm damn proud of you guys in the comment section. That is absolutely correct, if the radiator is NOT getting hot enough(lack of sufficient coolant flow) that fan will never kick on to begin with. These German vehicles are notorious for impeller issues. Awesome job guys!
Thank you so much for this video. I was able to test and diagnose why the fans were not working on my '04 Jetta 1.8t. I found no power getting to the thermo switch and found the contacts on fuse 8 were melting and corroded. Cleaned the contacts and works great. Thank you again.
Paul, good to see you have such a smart apprentice for his age! Great circuit testing and I haven't watched the part two yet, but I suspect like others that you may have a loose/broken plastic impeller. Common on these and easy to miss, specially when it's had all that work. Best wishes from Vancouver, and wave HI to May for me.
I know some other guys have said it but from my experience with those cars its prolly the plastic water pump impeller broke. Usually you can take out the thermostat and see the back of the pump to see if its broke. as usual another fantastic video brother.GOD bless.
Hi mate im trying to figure my issue out ..ive not heard my fans kick in fir a while ive put a new ac condensor jn and new rad i done pump sensor(but not genuine coolant sensor im getting an oem this week ) new thermostat oem new belt . Flushed twice now new coolant . Ive now started to get good warmth at lower hose . But occasionally exp tank stays a smidge high after cooling . Not much but over max mark ..and at times i syphon excess into rad ..oil is fine not long changed it with filter ..old water pump was ok to but changed it anyway . No leaks ..i eondered if it was my ambient temp sensir as it affects hvac sustems I tried to undo the coolant sensir today to bypass but the clip i need to push on is on otger side and alternator etc in the way inc housing etc..was a pig to change ..beltt off alternator off top tensioner bolt ggrr
great tip Thomas, I missed the coolant flow to the reservoir comment. I will have Pete check that right now. Also sorry I missed that variable in the video.
hi dan when i bridge a connector block i like to connect the jumper wire to the load connector first and the supply connector last to reduce the chance of a short circuit (blown fuse) by the loose end of the jumper wire. great video thanks again.
So, my 2000 Audi TT Quattro has no fans. And I’ve pinpoint no low fan being cause by a faulty fan switch. I’ve delidded a control module an have found, even with ac, I have no high fans. The high relay closes with the ac clutch relay in the module, and even doing it manually without ac, no high fans. Where should I check as to why I have no high fans? (Currently still have the faulty fan switch installed).
Just check continuity at the fans, I have continuity on low circuit but none on high. Both fans have a red-black wire (low fan power), a red-white wire (high fan power), and brown-Black wire (ground). Correct me if I’m wrong. But, red-black to black-brown read continuity while red-white to brown-Black read open. (This is true for both fans). I also power probed the relay connector. Bright light when testing the power side to ground on battery, dim when testing the ground side (or the side that feeds power to fan) to power from the battery. Ohms from module connection to fan connectors reads .2-.3ohms on both fan connectors and for both high and low circuits. Am I too assume that the high side in my fans are my problem for no high fans? I just don’t understand how I have 12volts across the control’s connectors with everything buttoned up, but basically looks like OL when isolating the fans. Possible short to ground would do that, but then the fuse 16(?) atop the battery would pop cause nothing else gets powered to act as a load. And I can’t see myself missing/improper contact with my meter on both fans but still having proper contact on low speed on both fans. I even tested three times to make sure. (Unless I was wrong about the wiring as stated above.)
Great video mr Danner, big five to your helper,just one question,can I use a power probe? For this bypass test,thank you again and cheers from ontario ca,
Awesome video, easy to learn, i have one question, the thermo fan swicth have 3 +wires where is located the ground??? Because i really need to clean that bolt ground thanksss a lot, grettings from Honduras,,
Great video. I was struggling to figure my fan issue again in my wife's New beetle and this video is the solve. Thanks again. Great to see you involving the young man in the video,
I connected to the battery the red thick one on negative and the other two on plus at a time. The white/red thick one made the small fan turn. The thin yellow/red one did not spin nothing. I have a big fan problem but now the small fan won't spin...may be cos its 5 celsius outside..or I fried the relay or what?
Hey, thanks for the info in the video.....tested found (facing car Right fan) not coming on... Do you have site where I can find the acceptable ranges for Reading from OBDII like (Oxygen Sensor)..etc Thanks....
It is becoming more and more difficult to answer questions here. I have 80,000 people asking me for help now. So I have created a forum to help you guys better. It is free to join and we can exchange pictures, wiring diagrams and waveforms if needed to help guide you through the process of troubleshooting your vehicle. Thank you so much! Hope to see you there. Paul Danner (ScannerDanner) www.scannerdanner.com/forum/post-your-repair-questions-here.html
Hi Paul...I want to know that what activates this coolant fan thermal switch??? Is it the temperature of the radiator or does the coolant temperatur sensor activates it??? Thank you.
I had the same problem, you have to get under the car and lift the little plastic clamp with a screwdriver in order to pull that triangular plug out. In my case it was the big fan motor, I disconnected it's plug and put an Ohm Meter across it, but it was an open circuit on both speeds / coils. After that I took the fan out, it was held with 3 Torx T30 screws and disassembled the back of the motor, it was a two man job, someone has to hold the fan so you won't brake the plastic fan and someone has to use a screwdriver and a hammer to pry apart the back of the motor (where the wires come out) I have finally discovered that the charcoal on one side got stuck, it wasn't sliding properly. I blew some air and moved it with my hand a little bit until it went smoothly. I assembled the motor and checked it's resistance again and it was about 1 Ohm, put it on a 12V power supply and it worked on both speeds
Thanks Paul i am going to work tomorrow on a volkwagon beetle 2.0 2002 and the cooling fans donot turn on.. Some time they do.. I run across your video. Thanks it will help me alot with the diagnostic.. Thanks from Franco Perez.. God bless you..
nothing happens when i bridge either of the connectors on the thermal switch connector, does that mean i have a power supply issue to the thermal switch?
Great video. I drive a 2000 jetta, and it's giving me the same problem. I had to change both fans, control module, upper and lower switches but still the fans wouldn't kick in. I took it to a local radiator shop for them to test if the head gasket was blown or not but unfortunately they couldn't run the test because the water bottle was clogged with oil. I took it to my mechanic, he told me he suspects the oil cooler might be the problem. My question is, does the oil cooler have anything to do with the fans not working?
for sure if oil cooler on oil filter housing letting engine oil into G12, would mimmick a blown head gasket... a simple 100 fix turned into a nightmare..junk the car or try a new head gasket, and then, problem not solved..so many 1.8 T audis and VWs in junk yards, for so many "compound possibility failures" That's the way car co's get us to just give it up and buy a newer car..from Audi / VW or some Japanese co..they don't care, the Japanese have the same strategy..have some failure modes that get the car to the junk yard ... !!! oil in coolant. trans dies, timing belt jumps..VW Audi do not care.. as long as after warranty..design it to bring to dlrs for $$$ and nightmare failures, or just to the junk yard..
when I check the fan by rewiring on the connector from the temperature sensors, the fans work for 2.3 seconds and stop working, what could be the problem Thanks in advance
nice video Paul I did not see the link for the head gasket, what is the name of the tool (software) you were using to draw on the diagram at the beginning?? thank you
Nice work again Beau! I assume your splitting your fee with him Mr D? You could check for water pump operation on any VW due to impellers falling off. You want to see flow into the expansion tank from the small pipe. Great video, thanks as always.
great tip! I will call Pete and have him check that right now. So to be clear, there should be flow on that smaller hose all the time regardless of t-stat opening or closing?
What a pleasure to watch your razor-sharp troubleshooting, Mr. Danner. Thanks to your very logical process, as well as reference to the schematic in your video, it's now obvious why our '03 Jetta 1.8t's, no-fans-at-all problem was such a poser... not only the Fan Control Module failed, but the Coolant Temp Sensor as well. That's what threw me - Pulling up the fans red/white, low-speed circuit got them both spinning, but no hi-speed fan operation... Sure - Both were bad! Again, thanks a million. BTW, what is that killer laptop application you use in the video? Man, would that ever be nice to have.
I had both fans not running. Step 1 is to pull fuse 16 from the fusebox by the driver door. Contact on and both fans are running, so fan motors are both good. Step 2 is to check the airco system. If it's pressure is too low, both fans will not run. You can look this up in VCDS 08 Airco/Heating > Advanced Measurements (or something like that) > select Compressor from the selectboxes. If it has the value 3, it means the fans are not running because sensor F129 provides information that the airco system pressure is too low. This will result in the A/C clutch not engaging, and both fans not running. My car just needed a airco service.
Bo is awesome, I wish my son would come to work with me. On a side note, it’s amazing how many stab marks and broken connectors we come across as Diag techs, it’s scary.
Thought i had you for a minute. Then at the end you made the comment about the t-stat. Recently had a Honda civic with same issue. Another shop tried fan temp switch and fan. Found bad t-stat. Fan switch was on cold side of t-stat even though temp gauge sensor was on hot side. Never understood why any manufacturer wouldn't put controls on engine side.
Good afternon my man !! How were your leads conected when you did the test it does not show that on the video ? The one u put on power was that conected to battery positive and the other one to ground ?
By jumping, and both high and low speed fans are working correctly, you would need to replace the fan switch? If the fans do not come on, Fans need to be replaced?
Hey great video!! Kids lucky to have Learnings at a young age.. So my issue I have that the low speed comes on but when I put my power to high speed nothing happens, fan don't move, what do you reckon it could be? Sounds like a silly question thanks
Hey man I just bought a 2003 Volkswagen Golf and I’m trying to figure it out how to put my relay on my fan because the guy who I bought the car too is he just by past it without the relay which is the switch(manual switch) keeps on burning and I just bought a switch again
Hello I found your video very informative with the wiring print. I have a bentley vw book that has the wiring diagrams but the one you were displaying was excellent. Just wondering how I could get to different wire diagrams. Is there a windows program I can purchase. Any Information you could pass on to me I would appreciate it. Just a garage mechanic that maintains a lot of vehicle for people. Thanks Patrick
Here is the DIY version of the program I use. Same diagrams but black and white, which is really not a big deal imo eautorepair.adtrk.biz/?a=10817&c=24&p=r&s1= $20 for your car for 30 day access and you can print everything
I've always done it hot, I've seen many circulate when it's cold as it is the bypass, I can't say for sure on that Golf, giving you poor information. If the impeller has indeed come off, there won't be any flow through the pipe hot or cold. Hope this helps.
ScannerDanner Makes you wonder why someone was probing the wires. Maybe they tested the switch when they had the radiator out and it tested good? From there they were lost.
Hey Paul, another really great vid. Just one small thing. You said at the end of the vid that the chemical test kit for finding head problems tests for hydrocarbons but it actually changes colour in the presence of Carbon Monoxide. This is all its designed to check for. :)
Steve A The one I am holding in my hand says that the liquid will change colour in the presence of (CO) Carbon Monoxide. I'm sure there are others that react with CO2 but I have not yet seen one that reacts with hydrocarbons.
Any advice for taking that connector off of the plug? My 2002 Golf has been having a problem with the fans running whenever the key is in the ignition so I feel like this could be part of the problem.
Sometimes I will intentionally ground the coolant sending unit, depending on the design just to re-create an overheat condition(verify if PCM responds by operating cooling fans in fail safe mode) It is imperative that the PCM sees the condition as well so 'tricking' it sometimes is also beneficial. Just be cautious that you don't cause engine damage from excessive heat.
I can see there is Green coolant in the expansion tank, VW need a specific type, that’s what the G12 means on the graphic on the side. G12 is pretty bright pink. I bet there’s been too much corrosion going on all through that motor and that’s what the root issue is.
when I say overheat. I should clarify, the needle dances over the middle line where it usually holds. it only does that in traffic or red light. But it also happens right away drive a mile and it's dancing. dosent go to far to the right.
I have to get this off my chest. On off road utility vehicles(we don't just work on automobiles) I have actually removed the radiator fan temp switch and used a small butane torch to heat it up and see if it functions(closes, continuity on a ohmmeter) Sort of a crude method but hey, I often have to improvise.
Sir thank u for the video .. Its very informative... I had problem .. With high speed fan... I do the same things with u Jump the wire at thermoswitch.. Low speed are good But at high speed doesnt work... Can u explain what should i do next... Is it control module problem ... Thanks for support .. Andsorry for my bad in english... Greetings from jakarta .. Indonesia
quick question I have an 02 jetta vr6 . my fans stopped working on me. I have checked for power on the red wire but when I jump it to check the high and low speeds nothing happens what else can it be ?
What tools do you use in this to put power to the fans and test if they work? I’m needing to do some fan troubleshooting on my 2004 Audi. Can’t find the right electrical testing probes anywhere!
I don't remember using any special tools in this video? Just my test light, but I do have tool pages that you can look at that show most of my equipment. www.aeswave.com/scannerdanner-c512/ www.amazon.com/shop/scannerdanner
Without looking at a diagram and knowing exactly what you did and how you did it, I cannot answer. Post this to my forum www.scannerdanner.com, it is free to join and we can absolutely help you there.
pin 1 and pin 2 make low fan run, but on my car pin 2 and pin 3 will not make the high-speed run, I change the fuse box by the battery and the module, any idea??? thanks
hey . i have asked on a few forums but havent had much luck . my fans dont come on even with air con turned on . My understanding is they should come on slow speed , i havent had overheating yet. I have had a new temp sensor fitted along with a new thermostat . i have tried the jumping like you showed . and fans kick in so would this suggest the switch ? thanks
Brooo omg YOU HAVE THE DIAGRAM for me! I have been struggling with both fans running on fast speed the second you thrn ignition and after turning ignition off they will run for like 10 more min. These will help me so much narrowing down my options!😁
For future needs. You can pay $20 for all of the service info for your car. However Mitchell is weak on Euro. eautorepair.adtrk.biz/?a=10817&c=24&p=r&s1= The diagrams are the same as what I'm showing you. The service info (description, operation etc) is typically weak on Euro stuff.
What if your high speed fan runs when you shut the car down? The fan isn't running when the car is on due to the temperature being pretty low ~160 C. When I pull the 30amp fuse #S180, the fan stops. I assume because the relay is then disengaged.
Great videos I wish I my dad got to teach me some car skills, awesome..! I have a 2003 gti and I can't get the drivers side fan to work to get my a/c started. I installed new fans, FCM and pressure switch. Fuse and connections are getting power. Passenger fan works with a/c and when temp goes up to cool car. My friend and I think it is the cooling fan switch on the radiator. You mentioned in the video it was kinda a hassle to remove do you have any pointers. And any other suggestion on why more a/c fan is not kicking on? Thanks you for your time and help. Can't wait to see more videos..!
Hey man, Very informative video.. well done, specially little champ did a good job! Quick question, when you apply that direct connection to the fan, i tried the same but the fans dont work. Does that mean fan control module box can also be an issue? I hear a tik sound from that when i give a direct connection to fans!
Hi sir m having issue with my fan , actually its start immediately while i swith on key, and showing error code p1672 in scanner, and showing error Circuit / Short To Gro
I have a similar problem. My cooling fans they don't work, but both radiator hoses, top and bottom, they get hot, and according to the vagcom, the temperature climbs with the engine running. Also i did the overheat test via vagcom, and the fans they did not spin! At this point i was thinking that it was the fan switch on the rad. But on this video i noticed one thig! The AC clutch wire! My AC clutch doesn't engage also but, the ECU compensates with the higher RPM. Following the scematic, the AC clutch wire goes to the coolant fan control module. Problably i have a bad coolant fan control module. Mine's a Skoda Octavia 1.6, it's the same car as a vw golf or a Audi A3
Júlio Garcia did you replace fans ? if both fans did not work did you unhook fan and test before proceeding? the blue wire if I remember correctly number 9 on the 14 pin connector makes the rpms jump and it is for wide open throttle WOT only but no power to ac clutch could be that the low speed on fans or shot the resistors failed inside of the fan motors.use a jumper wire to the brown on ac clutch and see if it engages. also check for 12v from ac controller to 14 pin connector I think it #10 red wire.
mronemanband1 No, the fans were not replaced, they are good, but i had like a domino efect. The thermal-switch of the fans was bad, and the fan controler module was also bad. One giveaway was that the 12v pin on the fan module, compared with the others, showed signs of a overload. in some areas of the pin was "coloured". For start i asked what was the price of a new one on the parts store, and they told me, with tax, 270 euros. At that time i decided that it was worth repair it. It was repaired, by a fraction of a new module. A small component inside the module had failed due to the overload. Now everything works, fans and the ac.
+mronemanband1 my 2000 jetta 4 is giving me a headache. Both fans stopped working, as a result water bounces back into the water bottle boiling hot. I have changed both fans, control module, upper and lower switches and still the fans won't kick in. I decided to take it to a local radiator shop to see if the head gasket is blown or not, unfortunately they couldn't run the test because my water bottle was clogged with oil. I took it to my machenic, he says he suspects the oil cooler might be faulty. My question is does the oil cooler have anything to do with the fans not working?
It looks like you broke the wiring connector? Like you I'm having trouble getting the connector off and I don't want to break it. Do you have any advice?
I did! Good eye. My suggestion is to find another connector you can see with the same style and experiment with it so you know what it should do. I believe the ECT that is on the T-Stat housing uses the same connector and is easy to see. Once you know how it is supposed to open, then you can work with the other one by feel. Oh and yes, I still broke it. It would NOT release no matter what I did. Nothing a little RTV won't hold together when your done :). (not in the electrical part of the connector of course) I like RTV for two reasons. 1. it holds great 2. it isn't permanent (you can still pull it apart in the future)
hi my friend i'm from chile and i saw your video..i have a passat v6 2004 and the fan is working on start in cold it runs always in high speed .do you know if this test will help.me? i changed the termostat and the problem dont stop
+casaborg post your tech help questions here. I have a lot of Euro guys over there willing to help. Thanks! www.scannerdanner.com/forum#/general-repair-questions/
got a question i did this test on my golf and the small fan works but big one doesnt .. this is on low and fast speed do i need new fans ? also took my thermostat out boiled it into a pan and it did not open
Dan, I am going to refer you to another channel for your specific VW questions. 1. Positve Lead Diagnostics (Tommy Wolfe is a former student of mine and current VW master) ruclips.net/channel/UCiFSILHjs5XZecZJDwn7ieA He is eager to help too! Tell him I sent you.
I'm late to the party, but yes broken impeller definitely. I'm also not a big fan of the aftermarket metal impeller pumps either. Btw, I didn't like the way the fans sounded either. One of them sounds like it is creaking, which I have seen happens because the magnet will actually spin in the housing.
Was thinking about the block test kit and I have run into vehicles where it wasn't accurate. Thinking about building a combustion gas detector using the guts from a cheap carbon monoxide detector that you can buy at any hardware store. Maybe stick in in a PCV pipe that is vented at the top.
@scanner denner i am having vw polo 2002 petrol how do i know my fan working properly but my car neaver heatup so means fan working ok if i want to c them working how i can cc them when can stationery position thanks
It is becoming more and more difficult to answer questions here. I have 80,000 people asking me for help now. So I have created a forum to help you guys better. It is free to join and we can exchange pictures, wiring diagrams and waveforms if needed to help guide you through the process of troubleshooting your vehicle. Thank you so much! Hope to see you there. Paul Danner (ScannerDanner) www.scannerdanner.com/forum/post-your-repair-questions-here.html
dude, you say it took you a while to get the connector off ... I past a while hours ago. I am about to hit it with an axe. Not everyone knows as much as you. How Do You get It Off?
I clicked on the video because of the fan problem, i watched it because of you being so nice to your son, to get him know about everything, it so nice
I love how you are teaching your son with patience.
You make it look so easy. Beau has one hell of a dad. You're both awesome. Great job.
This was such a great video man! Love how you showed your son step by step and mostly me as a viewer. Some people don't even do that. I appreciate this video so much! Great job and thank you!
Thank you so much!
So good to see your son working with dad ...your so good with him passing on your knowledge and he asks some great questions aswell great video helped me out a lot👍👍👍👍
He said awesome when the fan came on when he touched that connection. He will remember that forever. That’s so good to get your young kids out to do this stuff. He might become an electrical engineer now.
It's getting dusty in here. A problem solver is born. Thank you for sharing.
Great test and teaching your son . I just mentioned your advice on testing a fuse on my ac and fan on my tdi jetta . I changed out the module I had a spare and no clue how this system lol and that did not fix it . It was a fuse on top of battery that would light up a test light but it had the crusty on the blades of fuse . Cleaned the blades and sure enough the fans worked ac came on . So after that I thought well Paul said under a load while I drank a cold beer . Lesson learned thanks for all you do
Well done- this is thumbs up for Mr. Beau Danner - hope to see you again helping your dad and asking lots of questions so you can learn just like we all do. Great Job Beau
Say man ur one hell of a teacher/instructor/ guide etc. Love the way ur level headed enuff to stay connected to Beau and to answer him correctly. And Beau is on point as can be he was recording ur every word which was why he thought ur statement was contradictory about whether hot was good or bad. Great question good answer. Really appreciated this video this morning..
Thanks so much!
I'm damn proud of you guys in the comment section. That is absolutely correct, if the radiator is NOT getting hot enough(lack of sufficient coolant flow) that fan will never kick on to begin with. These German vehicles are notorious for impeller issues. Awesome job guys!
Most informative video ive ever seen. Your son is lucky to have a dad like you. He will be a great mechanic one day if that's what he chooses to be.
Man, this is an awesome video. Spent hours on fourms reading with no luck. Your video helped me tremendously! Thank you !!!
The best explanation of the vw fan circuit!! Thank you!!!
Great video very straight to the point troubleshooting diagnosis.
Thank you so much for this video. I was able to test and diagnose why the fans were not working on my '04 Jetta 1.8t. I found no power getting to the thermo switch and found the contacts on fuse 8 were melting and corroded. Cleaned the contacts and works great. Thank you again.
Paul, good to see you have such a smart apprentice for his age! Great circuit testing and I haven't watched the part two yet, but I suspect like others that you may have a loose/broken plastic impeller. Common on these and easy to miss, specially when it's had all that work. Best wishes from Vancouver, and wave HI to May for me.
I know some other guys have said it but from my experience with those cars its prolly the plastic water pump impeller broke. Usually you can take out the thermostat and see the back of the pump to see if its broke. as usual another fantastic video brother.GOD bless.
Hi mate im trying to figure my issue out ..ive not heard my fans kick in fir a while ive put a new ac condensor jn and new rad i done pump sensor(but not genuine coolant sensor im getting an oem this week ) new thermostat oem new belt .
Flushed twice now new coolant . Ive now started to get good warmth at lower hose . But occasionally exp tank stays a smidge high after cooling . Not much but over max mark ..and at times i syphon excess into rad ..oil is fine not long changed it with filter ..old water pump was ok to but changed it anyway . No leaks ..i eondered if it was my ambient temp sensir as it affects hvac sustems
I tried to undo the coolant sensir today to bypass but the clip i need to push on is on otger side and alternator etc in the way inc housing etc..was a pig to change ..beltt off alternator off top tensioner bolt ggrr
Broken water pump impeller... check for coolant flow back into the reservoir. No flow, needs a water pump.
great tip Thomas, I missed the coolant flow to the reservoir comment. I will have Pete check that right now. Also sorry I missed that variable in the video.
ScannerDanner We can't think of everything all of the time... I'm excited to maybe having been of help!
*****
absolutely! thanks again
Pretty sharp Thomas- you are the guru when it comes to VW. Fantastic channel as well, I have learnt soooooo much .
Steve Rob Thanks for the plug!
hi dan when i bridge a connector block i like to connect the jumper wire to the load connector first and the supply connector last to reduce the chance of a short circuit (blown fuse) by the loose end of the jumper wire. great video thanks again.
So, my 2000 Audi TT Quattro has no fans. And I’ve pinpoint no low fan being cause by a faulty fan switch. I’ve delidded a control module an have found, even with ac, I have no high fans. The high relay closes with the ac clutch relay in the module, and even doing it manually without ac, no high fans.
Where should I check as to why I have no high fans? (Currently still have the faulty fan switch installed).
Just check continuity at the fans, I have continuity on low circuit but none on high.
Both fans have a red-black wire (low fan power), a red-white wire (high fan power), and brown-Black wire (ground).
Correct me if I’m wrong.
But, red-black to black-brown read continuity while red-white to brown-Black read open. (This is true for both fans).
I also power probed the relay connector. Bright light when testing the power side to ground on battery, dim when testing the ground side (or the side that feeds power to fan) to power from the battery.
Ohms from module connection to fan connectors reads .2-.3ohms on both fan connectors and for both high and low circuits.
Am I too assume that the high side in my fans are my problem for no high fans?
I just don’t understand how I have 12volts across the control’s connectors with everything buttoned up, but basically looks like OL when isolating the fans. Possible short to ground would do that, but then the fuse 16(?) atop the battery would pop cause nothing else gets powered to act as a load. And I can’t see myself missing/improper contact with my meter on both fans but still having proper contact on low speed on both fans. I even tested three times to make sure.
(Unless I was wrong about the wiring as stated above.)
This is so awesome. Teaching your son at a very young age. I have a lot of respect for you guy, Keep up the good work.
Still a great video eight years later!
Great video mr Danner, big five to your helper,just one question,can I use a power probe? For this bypass test,thank you again and cheers from ontario ca,
Awesome video, easy to learn, i have one question, the thermo fan swicth have 3 +wires where is located the ground??? Because i really need to clean that bolt ground thanksss a lot, grettings from Honduras,,
Great video. I was struggling to figure my fan issue again in my wife's New beetle and this video is the solve. Thanks again. Great to see you involving the young man in the video,
I connected to the battery the red thick one on negative and the other two on plus at a time. The white/red thick one made the small fan turn. The thin yellow/red one did not spin nothing. I have a big fan problem but now the small fan won't spin...may be cos its 5 celsius outside..or I fried the relay or what?
Hey, thanks for the info in the video.....tested found (facing car Right fan) not coming on...
Do you have site where I can find the acceptable ranges for Reading from OBDII like (Oxygen Sensor)..etc
Thanks....
It is becoming more and more difficult to answer questions here. I have 80,000 people asking me for help now. So I have created a forum to help you guys better. It is free to join and we can exchange pictures, wiring diagrams and waveforms if needed to help guide you through the process of troubleshooting your vehicle. Thank you so much! Hope to see you there.
Paul Danner (ScannerDanner)
www.scannerdanner.com/forum/post-your-repair-questions-here.html
Where did you get the wiring diagram? (what 's the name of the package)looks to be clear and easy to read.
thankyou
droopy761 www.scannerdanner.com/forum#/20150619/where-to-get-wiring-diagrams-4839109/
Hi Paul...I want to know that what activates this coolant fan thermal switch??? Is it the temperature of the radiator or does the coolant temperatur sensor activates it??? Thank you.
Way better than VW vortex explanations I found.
I had the same problem, you have to get under the car and lift the little plastic clamp with a screwdriver in order to pull that triangular plug out.
In my case it was the big fan motor, I disconnected it's plug and put an Ohm Meter across it, but it was an open circuit on both speeds / coils.
After that I took the fan out, it was held with 3 Torx T30 screws and disassembled the back of the motor, it was a two man job, someone has to hold the fan so you won't brake the plastic fan and someone has to use a screwdriver and a hammer to pry apart the back of the motor (where the wires come out)
I have finally discovered that the charcoal on one side got stuck, it wasn't sliding properly.
I blew some air and moved it with my hand a little bit until it went smoothly.
I assembled the motor and checked it's resistance again and it was about 1 Ohm, put it on a 12V power supply and it worked on both speeds
I do exacly what u just did. I find out that when I test the red/power to the red/yellow the fan don't run. what now?
Thanks Paul i am going to work tomorrow on a volkwagon beetle 2.0 2002 and the cooling fans donot turn on.. Some time they do.. I run across your video. Thanks it will help me alot with the diagnostic.. Thanks from Franco Perez.. God bless you..
Make sure you watch part 2!
nothing happens when i bridge either of the connectors on the thermal switch connector, does that mean i have a power supply issue to the thermal switch?
Great video. I drive a 2000 jetta, and it's giving me the same problem. I had to change both fans, control module, upper and lower switches but still the fans wouldn't kick in. I took it to a local radiator shop for them to test if the head gasket was blown or not but unfortunately they couldn't run the test because the water bottle was clogged with oil. I took it to my mechanic, he told me he suspects the oil cooler might be the problem. My question is, does the oil cooler have anything to do with the fans not working?
for sure if oil cooler on oil filter housing letting engine oil into G12, would mimmick a blown head gasket... a simple 100 fix turned into a nightmare..junk the car or try a new head gasket, and then, problem not solved..so many 1.8 T audis and VWs in junk yards, for so many "compound possibility failures" That's the way car co's get us to just give it up and buy a newer car..from Audi / VW or some Japanese co..they don't care, the Japanese have the same strategy..have some failure modes that get the car to the junk yard ... !!! oil in coolant. trans dies, timing belt jumps..VW Audi do not care.. as long as after warranty..design it to bring to dlrs for $$$ and nightmare failures, or just to the junk yard..
Hey, what is wrong if I get low speed working normally, but when I try the red/ yellow high speed, I get nothing? Still a bad thermal switch?
Wooow!!! There is the name of my country written on the coolant hose at 7:25 . This is the 1,8T engine made in Győr, Hungary!
when I check the fan by rewiring on the connector from the temperature sensors, the fans work for 2.3 seconds and stop working, what could be the problem
Thanks in advance
great video, what if my high fan is not working? did the same excat trouble sgooting as you did. where should i go after tht...
What's the easiest was to remove the switch? I've been trying from under the car and no luck. Thanks in advance.
nice video Paul I did not see the link for the head gasket,
what is the name of the tool (software) you were using to draw on the diagram at the beginning?? thank you
Nice work again Beau! I assume your splitting your fee with him Mr D?
You could check for water pump operation on any VW due to impellers falling off. You want to see flow into the expansion tank from the small pipe.
Great video, thanks as always.
great tip! I will call Pete and have him check that right now.
So to be clear, there should be flow on that smaller hose all the time regardless of t-stat opening or closing?
What a pleasure to watch your razor-sharp troubleshooting, Mr. Danner. Thanks to your very logical process, as well as reference to the schematic in your video, it's now obvious why our '03 Jetta 1.8t's, no-fans-at-all problem was such a poser... not only the Fan Control Module failed, but the Coolant Temp Sensor as well. That's what threw me - Pulling up the fans red/white, low-speed circuit got them both spinning, but no hi-speed fan operation... Sure - Both were bad!
Again, thanks a million. BTW, what is that killer laptop application you use in the video? Man, would that ever be nice to have.
I had both fans not running. Step 1 is to pull fuse 16 from the fusebox by the driver door. Contact on and both fans are running, so fan motors are both good. Step 2 is to check the airco system. If it's pressure is too low, both fans will not run. You can look this up in VCDS 08 Airco/Heating > Advanced Measurements (or something like that) > select Compressor from the selectboxes. If it has the value 3, it means the fans are not running because sensor F129 provides information that the airco system pressure is too low. This will result in the A/C clutch not engaging, and both fans not running. My car just needed a airco service.
What would I do if one fan don't work? In my case the high speed.
J. R. Puón did you ever figure out what this problem was?
Bo is awesome, I wish my son would come to work with me. On a side note, it’s amazing how many stab marks and broken connectors we come across as Diag techs, it’s scary.
Thought i had you for a minute. Then at the end you made the comment about the t-stat. Recently had a Honda civic with same issue. Another shop tried fan temp switch and fan. Found bad t-stat. Fan switch was on cold side of t-stat even though temp gauge sensor was on hot side. Never understood why any manufacturer wouldn't put controls on engine side.
Good afternon my man !! How were your leads conected when you did the test it does not show that on the video ? The one u put on power was that conected to battery positive and the other one to ground ?
By jumping, and both high and low speed fans are working correctly, you would need to replace the fan switch? If the fans do not come on, Fans need to be replaced?
What would you have done if you didn't have the wiring diagram? Just thinking out loud here. Would it be harder to sort out?
Absolutely! I wouldn't even attempt to troubleshoot an unfamiliar system without a diagram
Hey great video!! Kids lucky to have Learnings at a young age.. So my issue I have that the low speed comes on but when I put my power to high speed nothing happens, fan don't move, what do you reckon it could be? Sounds like a silly question thanks
Hey man I just bought a 2003 Volkswagen Golf and I’m trying to figure it out how to put my relay on my fan because the guy who I bought the car too is he just by past it without the relay which is the switch(manual switch) keeps on burning and I just bought a switch again
When it's up to temp it should be circulating through the small pipe yes.
so it MUST be up to temp. to use this test? I just want to get my facts straight
Hello I found your video very informative with the wiring print. I have a bentley vw book that has the wiring diagrams but the one you were displaying was excellent. Just wondering how I could get to different wire diagrams. Is there a windows program I can purchase. Any Information you could pass on to me I would appreciate it. Just a garage mechanic that maintains a lot of vehicle for people. Thanks Patrick
Here is the DIY version of the program I use. Same diagrams but black and white, which is really not a big deal imo
eautorepair.adtrk.biz/?a=10817&c=24&p=r&s1=
$20 for your car for 30 day access and you can print everything
So if i jumper it and get low speed but no High speed……….what part is bad???
I've always done it hot, I've seen many circulate when it's cold as it is the bypass, I can't say for sure on that Golf, giving you poor information.
If the impeller has indeed come off, there won't be any flow through the pipe hot or cold. Hope this helps.
absolutely this helps a lot! I will advise to check it hot then. Really appreciate the support
ScannerDanner Makes you wonder why someone was probing the wires. Maybe they tested the switch when they had the radiator out and it tested good? From there they were lost.
You are the MAN SCANNER DANNER.ThankYou for all Your hard work.I have upped my game a lot just from watching Your videos.
Hey Paul, another really great vid. Just one small thing. You said at the end of the vid that the chemical test kit for finding head problems tests for hydrocarbons but it actually changes colour in the presence of Carbon Monoxide. This is all its designed to check for. :)
Carbon Dioxide
Steve A The one I am holding in my hand says that the liquid will change colour in the presence of (CO) Carbon Monoxide. I'm sure there are others that react with CO2 but I have not yet seen one that reacts with hydrocarbons.
Any advice for taking that connector off of the plug? My 2002 Golf has been having a problem with the fans running whenever the key is in the ignition so I feel like this could be part of the problem.
Sometimes I will intentionally ground the coolant sending unit, depending on the design just to re-create an overheat condition(verify if PCM responds by operating cooling fans in fail safe mode) It is imperative that the PCM sees the condition as well so 'tricking' it sometimes is also beneficial. Just be cautious that you don't cause engine damage from excessive heat.
I can see there is Green coolant in the expansion tank, VW need a specific type, that’s what the G12 means on the graphic on the side. G12 is pretty bright pink. I bet there’s been too much corrosion going on all through that motor and that’s what the root issue is.
also do i need to replace radiator or will that be fine just fans
when I say overheat. I should clarify, the needle dances over the middle line where it usually holds. it only does that in traffic or red light. But it also happens right away drive a mile and it's dancing. dosent go to far to the right.
I have to get this off my chest. On off road utility vehicles(we don't just work on automobiles) I have actually removed the radiator fan temp switch and used a small butane torch to heat it up and see if it functions(closes, continuity on a ohmmeter) Sort of a crude method but hey, I often have to improvise.
hi , plz help me i have in pin 1 négative pin 2 positive pin 3 positive it's normal ?
very helpful information here, intelligently explained also. thankyou and you are setting a great example for your kid
+B New thanks so much!
Sir thank u for the video
.. Its very informative...
I had problem .. With high speed fan... I do the same things with u
Jump the wire at thermoswitch..
Low speed are good
But at high speed doesnt work...
Can u explain what should i do next... Is it control module problem
...
Thanks for support .. Andsorry for my bad in english...
Greetings from jakarta .. Indonesia
Did you watch part 2?
quick question I have an 02 jetta vr6 . my fans stopped working on me. I have checked for power on the red wire but when I jump it to check the high and low speeds nothing happens what else can it be ?
+TrainedHotdog
No ended up junky the car
What tools do you use in this to put power to the fans and test if they work? I’m needing to do some fan troubleshooting on my 2004 Audi. Can’t find the right electrical testing probes anywhere!
I don't remember using any special tools in this video? Just my test light, but I do have tool pages that you can look at that show most of my equipment.
www.aeswave.com/scannerdanner-c512/
www.amazon.com/shop/scannerdanner
One question. My fans didn’t turn on high when I did the computer one. Do I have. Anda computer or??
Without looking at a diagram and knowing exactly what you did and how you did it, I cannot answer. Post this to my forum www.scannerdanner.com, it is free to join and we can absolutely help you there.
pin 1 and pin 2 make low fan run, but on my car pin 2 and pin 3 will not make the high-speed run, I change the fuse box by the battery and the module, any idea??? thanks
not without looking at a wiring diagram of your system eautorepair.adtrk.biz/?a=10817&c=24&p=r&s1=
What is the wiring diagram you used cause I need to figure out why my fan ain’t turning on.
Here you go eautorepair.adtrk.biz/?a=10817&c=24&p=r&s1=
Same diagrams I use
hey . i have asked on a few forums but havent had much luck . my fans dont come on even with air con turned on . My understanding is they should come on slow speed , i havent had overheating yet. I have had a new temp sensor fitted along with a new thermostat . i have tried the jumping like you showed . and fans kick in so would this suggest the switch ?
thanks
Brooo omg YOU HAVE THE DIAGRAM for me! I have been struggling with both fans running on fast speed the second you thrn ignition and after turning ignition off they will run for like 10 more min. These will help me so much narrowing down my options!😁
For future needs. You can pay $20 for all of the service info for your car. However Mitchell is weak on Euro.
eautorepair.adtrk.biz/?a=10817&c=24&p=r&s1=
The diagrams are the same as what I'm showing you.
The service info (description, operation etc) is typically weak on Euro stuff.
What if your high speed fan runs when you shut the car down?
The fan isn't running when the car is on due to the temperature being pretty low ~160 C.
When I pull the 30amp fuse #S180, the fan stops. I assume because the relay is then disengaged.
+johncuce223 how long does it run after shut down
+ScannerDanner It never shuts off.
good job Danner & little helper too ?
You can also rent that kit to check for combustion gasses in the cooling system from AutoZone.
Great videos I wish I my dad got to teach me some car skills, awesome..! I have a 2003 gti and I can't get the drivers side fan to work to get my a/c started. I installed new fans, FCM and pressure switch. Fuse and connections are getting power. Passenger fan works with a/c and when temp goes up to cool car. My friend and I think it is the cooling fan switch on the radiator. You mentioned in the video it was kinda a hassle to remove do you have any pointers. And any other suggestion on why more a/c fan is not kicking on? Thanks you for your time and help. Can't wait to see more videos..!
Hey man,
Very informative video.. well done, specially little champ did a good job!
Quick question, when you apply that direct connection to the fan, i tried the same but the fans dont work. Does that mean fan control module box can also be an issue? I hear a tik sound from that when i give a direct connection to fans!
PS) on red hot wire connection i still see 12.5V going down
Hi sir m having issue with my fan , actually its start immediately while i swith on key, and showing error code p1672 in scanner, and showing error
Circuit / Short To Gro
One more best and easy videos of you , and with a nice helper , and smart as his dad
I have a similar problem.
My cooling fans they don't work, but both radiator hoses, top and bottom, they get hot, and according to the vagcom, the temperature climbs with the engine running.
Also i did the overheat test via vagcom, and the fans they did not spin!
At this point i was thinking that it was the fan switch on the rad.
But on this video i noticed one thig!
The AC clutch wire!
My AC clutch doesn't engage also but, the ECU compensates with the higher RPM.
Following the scematic, the AC clutch wire goes to the coolant fan control module.
Problably i have a bad coolant fan control module.
Mine's a Skoda Octavia 1.6, it's the same car as a vw golf or a Audi A3
Júlio Garcia did you replace fans ? if both fans did not work did you unhook fan and test before proceeding? the blue wire if I remember correctly number 9 on the 14 pin connector makes the rpms jump and it is for wide open throttle WOT only but no power to ac clutch could be that the low speed on fans or shot the resistors failed inside of the fan motors.use a jumper wire to the brown on ac clutch and see if it engages. also check for 12v from ac controller to 14 pin connector I think it #10 red wire.
mronemanband1 No, the fans were not replaced, they are good, but i had like a domino efect.
The thermal-switch of the fans was bad, and the fan controler module was also bad. One giveaway was that the 12v pin on the fan module, compared with the others, showed signs of a overload. in some areas of the pin was "coloured".
For start i asked what was the price of a new one on the parts store, and they told me, with tax, 270 euros.
At that time i decided that it was worth repair it.
It was repaired, by a fraction of a new module.
A small component inside the module had failed due to the overload.
Now everything works, fans and the ac.
+mronemanband1 my 2000 jetta 4 is giving me a headache. Both fans stopped working, as a result water bounces back into the water bottle boiling hot. I have changed both fans, control module, upper and lower switches and still the fans won't kick in. I decided to take it to a local radiator shop to see if the head gasket is blown or not, unfortunately they couldn't run the test because my water bottle was clogged with oil. I took it to my machenic, he says he suspects the oil cooler might be faulty. My question is does the oil cooler have anything to do with the fans not working?
+Avukile Gxalo watch part 2
Hey mate,
You know whats the operational current for these fans?
Not sure my friend, sorry
This is a simple high amperage switch that switches the 12 volts to the fan directly. If it was ecu than it would be a thin wire
It looks like you broke the wiring connector? Like you I'm having trouble getting the connector off and I don't want to break it. Do you have any advice?
I did! Good eye. My suggestion is to find another connector you can see with the same style and experiment with it so you know what it should do. I believe the ECT that is on the T-Stat housing uses the same connector and is easy to see. Once you know how it is supposed to open, then you can work with the other one by feel.
Oh and yes, I still broke it. It would NOT release no matter what I did.
Nothing a little RTV won't hold together when your done :). (not in the electrical part of the connector of course)
I like RTV for two reasons. 1. it holds great 2. it isn't permanent (you can still pull it apart in the future)
Wich one is called the auxiliary fan the low speed or high speed?
auxiliary fan is usually for the AC condenser
Paul, that hyper link for the combustion tester isn't working. Or it's my iPad lol.
Great field work as usual!
hi my friend i'm from chile and i saw your video..i have a passat v6 2004 and the fan is working on start in cold it runs always in high speed .do you know if this test will help.me? i changed the termostat and the problem dont stop
+casaborg post your tech help questions here. I have a lot of Euro guys over there willing to help.
Thanks!
www.scannerdanner.com/forum#/general-repair-questions/
what if only one speed on the fan works
got a question i did this test on my golf and the small fan works but big one doesnt .. this is on low and fast speed do i need new fans ? also took my thermostat out boiled it into a pan and it did not open
Dan, I am going to refer you to another channel for your specific VW questions.
1. Positve Lead Diagnostics (Tommy Wolfe is a former student of mine and current VW master)
ruclips.net/channel/UCiFSILHjs5XZecZJDwn7ieA
He is eager to help too! Tell him I sent you.
Great vid mate. Very well explained and has helped isolate the problem I am having. 👍👍
I'm late to the party, but yes broken impeller definitely. I'm also not a big fan of the aftermarket metal impeller pumps either. Btw, I didn't like the way the fans sounded either. One of them sounds like it is creaking, which I have seen happens because the magnet will actually spin in the housing.
can any one tell me what is the name of that yellow wire he transfers power to the other side to power up the fand
It's just a jumper wire
Was thinking about the block test kit and I have run into vehicles where it wasn't accurate. Thinking about building a combustion gas detector using the guts from a cheap carbon monoxide detector that you can buy at any hardware store. Maybe stick in in a PCV pipe that is vented at the top.
@scanner denner i am having vw polo 2002 petrol how do i know my fan working properly but my car neaver heatup so means fan working ok if i want to c them working how i can cc them when can stationery position thanks
maybe with a scan tool with bi-directional controls, you can command the fans to turn on
+ScannerDanner thanks for ki d reply somy car is cool never heated so means my fan working thats why its nt heated ever and your son is genius :)
hi were did you get electric diagram
+Oscar Alarcon Mitchell On Demand
Thanks
hi there cool vdo, i have a question, on my car the high speed is not working ,any idea?
It is becoming more and more difficult to answer questions here. I have 80,000 people asking me for help now. So I have created a forum to help you guys better. It is free to join and we can exchange pictures, wiring diagrams and waveforms if needed to help guide you through the process of troubleshooting your vehicle. Thank you so much! Hope to see you there.
Paul Danner (ScannerDanner)
www.scannerdanner.com/forum/post-your-repair-questions-here.html
Thanks Paul
dude, you say it took you a while to get the connector off ... I past a while hours ago. I am about to hit it with an axe. Not everyone knows as much as you. How Do You get It Off?
great video!!! my fan is not working and I changed a fan, coolant temp sensor, and control unit (relay)
Make sure you watch the follow up to this. It was the water pump
Nice cool helpful video, I have a 1.8T I think GLI 2002 Jetta 5 speed.
I used a paper clip to jump it and nothing happened. So switch is shot? No fans no nothing. spark in one pin.