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
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👍👍👍👍
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!
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.
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
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.
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!
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
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..
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.
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
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.
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.
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,
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?
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.
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.
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.
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.
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.
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.
Ha. I've just done a 2002 AUDI TT 1.8 (almost identical wiring) with this exact problem, using this exact method. Apparently the modules go a lot, but this too was the thermoswitch. :)
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.
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'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.
possibly we will see. there is the possibility of a faulty water pump on this one that I was not aware of. so whether it be a video update or just in text form. I'll get you something
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.
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 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..!
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,
thts kool tht ur doin some euro cars now! those 1.8 t sure do have there share of problems but sme ppl say the german over engineer but they keep u on ur toes learning there designs! i though forsure it wld of been the fan module cuse they sure do go bad! anthr thing i like about euro cars is they use part numbers on everything! but dffnt thumbs up good stuff!!
I was wondering when I was going to see you comment Thomas...Sure only when it comes to the vw stuff hahaha.. Very good video Paul...,show us more euro stuff pretty please..lol
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
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, 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
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.
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!
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
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
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
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.
I tested the red/white to the red/yellow and the high speed fan wouldn't run. I tested the power/red to low speed and power/red to high speed and they both worked.
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?
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.
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 ?
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
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?
Thats how they run up your bill. Flushing it didn’t need and all the other stuff it didn’t need. Just put the switch on it and your done. There just ripping people off in these shops. Ive fixed these for $14 relay switch.
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
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?
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?
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.
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
You make it look so easy. Beau has one hell of a dad. You're both awesome. Great job.
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
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👍👍👍👍
I love how you are teaching your son with patience.
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!
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.
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
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.
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.
The best explanation of the vw fan circuit!! Thank you!!!
Great video very straight to the point troubleshooting diagnosis.
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.
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!
Man, this is an awesome video. Spent hours on fourms reading with no luck. Your video helped me tremendously! Thank you !!!
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
very helpful information here, intelligently explained also. thankyou and you are setting a great example for your kid
+B New thanks so much!
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!
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.
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
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.
Still a great video eight years later!
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.
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,
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?
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.
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.
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!
Way better than VW vortex explanations I found.
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.
Great vid mate. Very well explained and has helped isolate the problem I am having. 👍👍
One more best and easy videos of you , and with a nice helper , and smart as his dad
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.
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.
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.
Nice cool helpful video, I have a 1.8T I think GLI 2002 Jetta 5 speed.
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.
Ha. I've just done a 2002 AUDI TT 1.8 (almost identical wiring) with this exact problem, using this exact method. Apparently the modules go a lot, but this too was the thermoswitch. :)
Thnaks for making this video.. Helped figure out the fan on my Audi TT is not working
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!
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'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.
Looks like your son Beau is learning a lot! KEEP IT UP!
Are you going to do a follow up on this one?
Thank you!
possibly we will see. there is the possibility of a faulty water pump on this one that I was not aware of. so whether it be a video update or just in text form. I'll get you something
Great job I learn something today thank you and your helper.
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
Great diagnostic video!!! And you're a great dad!!! Keep up the good work 👍
High five too Bo from Sweden!!!
You can also rent that kit to check for combustion gasses in the cooling system from AutoZone.
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/
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.
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,,
Pete is a very lucky guy to have you!!!! tell him that please.
+estrelladelnorte1308 I will, thanks man
Good vid. A word of caution about the fan to the boy might have been a good idea.
Dude, thank you so much, that was very informative!
No problem!
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..!
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,
thts kool tht ur doin some euro cars now! those 1.8 t sure do have there share of problems but sme ppl say the german over engineer but they keep u on ur toes learning there designs! i though forsure it wld of been the fan module cuse they sure do go bad! anthr thing i like about euro cars is they use part numbers on everything! but dffnt thumbs up good stuff!!
Definitely an over engineered fan circuit
I was wondering when I was going to see you comment Thomas...Sure only when it comes to the vw stuff hahaha..
Very good video Paul...,show us more euro stuff pretty please..lol
Thank you very much for this video, I hope it helps me find my mk4 jetta fans problem. Cheers. (I like your assistant, he's a smart kid)
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?
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..
Thanks for the vid Paul. Thumbs up for Bo.
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
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.
Another good diagnosis. And a great helper also!
Wonderful video. Big up to your assistant
Really cool stuff teach your kids how to work and diagnose keep up the good 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
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
Paul, that hyper link for the combustion tester isn't working. Or it's my iPad lol.
Great field work as usual!
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
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
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
good job Danner & little helper too ?
Very good video, man! Ready to go out there and test this beotch...
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
Finally you got an easy one
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.
Good detailed and helpful video... thanks for sharing
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?
I tested the red/white to the red/yellow and the high speed fan wouldn't run. I tested the power/red to low speed and power/red to high speed and they both worked.
Thats my problem. I think just the alternator is gonna have to moved to get the thermostat out.
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 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?
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?
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.
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 ?
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
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's the easiest was to remove the switch? I've been trying from under the car and no luck. Thanks in advance.
Thats how they run up your bill. Flushing it didn’t need and all the other stuff it didn’t need. Just put the switch on it and your done. There just ripping people off in these shops. Ive fixed these for $14 relay switch.
Great info. Thank you both
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
hehe great helper :) I imagine how cool it must be for him to be working like that with You :) greets :)
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?
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?
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
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
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.