How to Troubleshoot and Fix the Porsche Radiator Fans

[@theplayernkc]

Another nice vid. FYI: If you have the Durametric tool, you can use it to test both Speed 1 and Speed 2 of the fans without starting the 986.

[@BurnersCars]

I did this before I owned a Durametric tool, but you are absolutely right. Now that I have the tool, I can say that using it makes diagnosing problems MUCH easier. I pinned your comment to help others.

[@ATLAS01COPCO]

Burner's Cars You said that if the AC is on both fans should run? Is that at slow speed. Thanks

[@ATLAS01COPCO]

I found out thanks

[@janetwatt7665]

I bought my 04 986 "S" a year ago (Feb 2016). I have watched many of Burner's videos and will say he is the best. Today..Feb 23rd here in Ontario our temps are 16c so super nice for us this time of the year. I removed the front bumper (without any problems) and have cleaned the rads. They were disgusting. Bird feathers mostly and stuff I couldn't recognize. Who needs a manual when Burner makes things so easy. Thanks man!

[@SaintElectroz]

Thanks! My Cayenne has been having the same symptoms and I've brought it to multiple places and we've yet to resolve this issue (fluctuating temperature + no A/C). Just wanted to say thanks for posting, this gives us a lot of information to work with!

[@scottsloan5743]

Burner, you motivated me to remove and replace the left aux fan on my 996. Your diagnosis was extremely helpful in determining that it as neither the high or low speeds, the fuses or resistor. It was, in fact, the fan. I would like to add to your commentary however, is that the reassembly is far more difficult than simply reversing the process. I would want anyone considering the procedure to pay particular attention to the orientation of the bowl shaped fan shroud and for the bracket is removed and how it might be reinstalled. Your video was excellent despite my mechanical shortcomings. It took me about six hours start to finish. That said, I hope it’s a long time before I have to repeat this on the right side. Thanks again and keep up the great work!

[@alexmax3]

Thanks for a nice video! Tip: if the temperature goes up, put the heater on maximum (don't stop the engine) and heater fan also to max. This helps at no matter which car and can save the engine (but you will sweat like in a sauna)

[@Matias_sebastian]

Honestly one of the most helpful video and videos I've come across. Great!

[@stevereeves4769]

A really great video. What caught my eye was my temp gauge on my 911/996 would creep up a little higher than I liked, just like the image you showed. I tested the right fan ballast today, low speed would not come on when I jumped the relay. Really appreciate this info, super helpful!

[@BurnersCars]

Awesome! Glad I could help, sir!

[@9jfd1]

I really enjoy the details you present for all the problems you face, I have same issue as my needle is slightly hotter than before, will follow same steps as you did thanks!!!

[@matthieugarcia9173]

Thank you ! I have the overheating problem and now, I know how to fix it ! Thank you from France

[@FelsvonDrago]

Thanks from Germany! Excellent video, with all relevant information and presented in an understandable way. I was able to replace my fans easily.

[@chrisdenning9225]

As a Porsche tech for over 30 years,I find your videos show the long way to test replace componants.The easy way to check coolant fan operation is to just turn the A/C on,both fans must run on speed 1,if not replace resistor.

[@BurnersCars]

Yes. That was the first thing I suggested under the troubleshooting section 3:10.

[@bigmacdaddy1234]

He did show that you dope.

[@SGliderGuy]

Overly critical eyes sometime miss the positive things.

[@EatSleepDrive]

Kudos for a great video. Super informative with the right amount of entertainment. This put my mind at ease after checking out a 911 which is having the same issue. Thanks for making the vid and I look forward to more!

[@franknutt1876]

Thanks for yet another great video. I'll be checking my 997. 👍

[@peterwelty]

Thank you for this! Exactly the case for me. Your video led to my making sense of my car.

[@rondetorres3842]

Having same problem with my '99 996.1, drivers side will not turn on with ac on or in high temp situations. Wasn't sure what made everything work together, but now I have a place to start and begin my process of elimination. If the fan comes on with a 12v source then the resistor is might be the problem. Great tutorial and thanks for posting!

[@FlavorDaver]

positive lead to the green wire, if no fan movement the ballast is bad.

[@rondetorres3842]

Had two bad ballast resistors and a bad fan. All good now. Thanks!

[@jax-tuner989]

I've discovered my fan that is not working by just putting my ear close to the vent. But it took a little while for me to know it.. Very nice video on this. Thank you Burner's Cars for inspiring me to fix it myself...I suggest that you should have tested the fan by simply tapping the 2 wires you cut into the battery to know if the fan motor is working.

[@BurnersCars]

Glad I could help! That would certainly work, but I didn't want to go cutting wires on the off chance that the fan was fine and it was something else (relay etc.)

[@24hourgmtchannel64]

Many complained about the 996 and 986 sharing the same components from the doors foward. I see it as a positive with used parts.

[@9jfd1]

Great details here well done! I found that you don't need to remove the shroud from the bracket, it is still possible to reinstall that way. Also my 2003 C2 cab did not have the battery drain hose in passenger side, maybe drivers side?

[@Marr_SC]

If one of your front rad fans won't go into high speed, it's likely a failed ballast resistor. I replaced one of these resistors on my front-right fan with a replacement resistor from DigiKey or Amazon (can't remember which) and it works perfectly. It was a ~$3 part after shipping. I want to say it was a 0.5 Ohm, 100 Watt resistor, but you should verify that before doing it yourself. And, as he mentioned, you will have to cut out the old resistor and splice in the new one, which isn't necessarily for everyone. I recorded the whole job, but I haven't been able to edit and post it yet. If you're having this problem, just Google "Porsche fan ballast resistor".

[@craigmartel5907]

Hi Burner, I got some info from another post and they said you can just change out the resister itself for about $4-$6 that are on Ebay. 100W x 0.5 ohm resistor

[@SGliderGuy]

Wondered how you determined it was .5 ohm? Did you measure a new OEM unit?

[@mickai.3689]

Perfect like always....looking forward...👍🏻

[@IttNeverTooLateToRace-qz2gn]

Very well done video, extremely clear, thank you. A question for you: I have the bumper cover off of my Boxster to do this because I'm doing some other things as well. When you remove the large metal bracket with the 2 - 13mm bolts and 1 - 13mm nut, won't the radiator drop with the bumper cover off unless you use something to tie it up and hold it in place?

[@raytracer1975]

Thanks for the great video! How long would it take to replace the fan?

[@damage98]

Great video, thanks for the education!

[@michaelphothong2252]

Great video! Very helpful. ? I have a air bag light on. Fault memory 28 and 30. Any help would be appreciated on a 1997 Porsche Boxster. (Ignition circuit-side airbase driver). Check the side airbags work and the clock spring work and the seat belt work. 🤔 Thank you!

[@bigmacdaddy1234]

Great video. Thanks!

[@jonnyreverb]

@8:17 Where would I find those plastic studs?

[@autoilu9000]

Hi! I noticed about a week ago that my Cayman S 987 right radiator fan did not work, another fan rotates at high speed in the 30s-60s cycles. I had seen your video in the past and it came to my mind almost immediately! Thanks to your good video I knew where to look but luckily I found that the stone was just stuck in the fan. I wonder if the breaks of the fans can be partly due to this jamming somehow odd that the electric motor is such a weak point?

[@BurnersCars]

I'm glad it was something simple, and I'm glad I was able to help! Interesting idea about junk jamming the fans... having cleaned the front radiators I can attest to just how much debris gets caught up in there.

[@edmclatchie2079]

Another great video. ps its sunny in London

[@BurnersCars]

Ha! Even London has better weather! It's quite the change from LA. Cheers!

[@stevereeves4769]

A follow up question. With great help from your video, I replaced a faulty right ballast (broken wire) and now all fans operate properly at low and high speeds. In summer city driving, temp gauge climbs to the middle of the 0 of the 180 degree shown on the temp gauge, as best as I can tell this is around the 200-205 temp range. At this point the fans come on. Is this a normal range for temp to climb to before fans kick in?? Per your videos, radiators/condensers have been cleaned and coolant changed. Thanks for all help!

[@BurnersCars]

Nice work, Steve! That seems a touch high. Nothing to worry about, but maybe worth investigating further. Do you have a Durametric tool or something that will get exact coolant temps? I believe they are supposed to switch on at low speeds around 97 degrees C and high speed around 103 C. If they're doing this, then I wouldn't worry about it.

[@stevereeves4769]

Thanks for additional insight/comment. I do have a infrared temp gun that can maybe help we verify actual temp, the car gauge going to the middle of the 0 of the 180 make is anybody's guess what that actual temperature is. W/o a/c being on, the temp climbs there before the low speed fans come on. Just wish they'd come on sooner. I'll test with temp gun and see what readings I get. Thank you for all help.

[@BurnersCars]

Yeah. The dashboard temp gauge tells you when something is really wrong, but for subtle changes, it can be a little harder to tell. Good luck!

[@Boxster330]

Awesome. Thank you.

[@matthewchubb1]

Hey Ben, I curbed my 986 badly and was watching this to see how I could remove the radiator between the fan and condenser. The condenser was totaled and I bought it's replacement already. Now I've seen broken pieces of the rad as well and need to do it, and hopefully I haven't destroyed the fan. It was pushed into the wheel well such that it was rubbing the wheel and could not steer. Debacle. Is it tough to do?

[@joejoe188]

What a pain in the butt! Great info and video!

[@pensionatoinkawasaki]

HI, you said that to check if the fans are working at speed1 it's enough to turn AC on. How to check if they work at speed2? My second question is the following: could the water pump being the cause of a small overheating?

[@mwong987]

good camera angles

[@scottsloan5743]

Is there any benefit, other than rad cleaning, to removing the bumper for the fan replacement? I’ve watched both those videos of yours and they’re excellent!

[@hurdigurdiman]

I have a serious overheating problem on my 99 996 911. The right one did not start. I changed the relays over (Two from the right changed two from the left) and exactly the same result. Left ok right no go so I take it that all relays are fine. . Are you sure that both sides should kick in the fan with AC on full manual or just the left side?

[@josephobrien1479]

Can you tell me where the engine compartment fan fuse and relay is? I have found one fuse related to The Engine Compartment Fan in the footwell (B4 which appears to be 15 Amp). Looking at the fuse diagram it appears C5 may also be related to the Engine Compartment blower fan Stage 1 which is 5 Amp. From what I see a standard type 53 12v relay is in the trunk which relates to The Engine Compartment Fan. Any thoughts or additional input on this?

[@tonynorman3780]

Looks to me like when you were undoing the top nut on that bracing strut the stud just sheared off - just like mine did!

[@evaforsaith6457]

Hi Ben. Have you thought of simply drilling a 5 cm hole in the plastic undershield directly below the coolant drain plug ? Saves taking that damn thing off . Not a problem ? OK . Just thought I would offer it up. Cheers from Oz.

[@Jaydaisky]

I just had my right fan replacing 3months ago 991.2 . But I just noticed that the left front fan is blowing a bit harder than the right one, but not as hard as when the temperature went up to “overheat” stage. Is that normal?? That both fan run at sightly different speed?

[@EchoRhythmMusic]

I have a ‘11 panamara and I’ve gone through 4 radiator fans in a year. I don’t know if it’s because I’m buying aftermarket fans or what but it’s frustrating

[@moybone6641]

Great job! You answered many of my questions. I think my left fan is not working on the low setting so I'll check my relays 1st. I've been wanting to clean my radiators too. Just going to wait for better weather. We're expecting bad weather in Seattle this weekend. (1999 986)

[@BurnersCars]

Ah, yeah, how about that storm? Having recently moved to Seattle from LA, I was expecting an awesome tempest...

[@moybone6641]

Welcome to Seattle. Me too but nada...

[@AverageGuy513]

Hm Nava most likely the resistor is bad. Happened to me. But you can check by junketing the relay and see if the fan turns on or not . Common problem

[@moybone6641]

Hey RK, will check that 1st. The HI setting works on both sides. I haven't had time to do the AC test to see if the LOW setting works.

[@AverageGuy513]

How did you check the HI setting? I am curious. Because it only turns on when the engine is super heated.

[@jamescarty2790]

My problem is that as soon as I start my 05 porsche cayenne v6 the rediator fan is running and that causes the engine to run too cool. What do you think is the problem.

[@wilbertpina3569]

** 10/14/2022** I hope you respond. Can I buy the same fan for both sides of my 2000 Porsche Boxster? Or do they have different fans? In regards to the relays is it best to buy the all new? Gracias big fan!

[@cheepGeek]

I decided to get the URO part from Rockauto. I usually get OEM parts, but I figured it's just a fan and there is nothing special about a fan. Every car has one. When I got it, I compared it with my Bosch fan and it functions just the same. Blows the same and has the same noise. So when my second fan blew, I had no hesitation to get another URO fan from Rockauto for half the price of the Bosch fan.

[@BurnersCars]

Makes sense. I'll be curious what the long-term durability is... but as long as it lasts at least half as long as the Bosch fan, you're still ahead, right?

[@cheepGeek]

URO stands for U Replace Often, but that's the fun of owning a Porsche, isn't it? Anyway, so far so good. The first one has been running 3 years without issue. I have a Durametric, so I can test at both speeds.

[@BurnersCars]

Haha! yep. But really, 3 years is not bad! Even if it only lasts another year or two, you'll probably get your money's worth... and it's not a big deal when they fail.

[@SGliderGuy]

@@cheepGeek LOL!

[@garyhelms1889]

Nice video!!

[@AverageGuy513]

I replaced both fans recently and also found vacuum leak due to hole in heater core after that the temperature at the traffic light does not go beyond 190. It used to be close to 215 prior to doing all these.

[@BurnersCars]

Nice work! When you say there was a hole in the heater core, do you mean it was leaking coolant? How did you find the problem?

[@AverageGuy513]

I was checking the vacuum on my coolant system (after flush) using AirLift and the system could not hold 25psi. So I started to investigate the issue and isolated the problem to heater core. Then I removed heater core and found coolant stains outside. After I swapped with a used on on ebay. The system could hold the vacuum at 25psi. I live in VA but got bought my 986 from bayarea. I am guessing Californians won't use heater much and the coolant is stagnant in the heater core to cause corrosion and leak. I guess you saved the ballistic resister since that part is good after swapping the fans. And expensive to buy later on as a replacement.

[@BurnersCars]

Ah, that makes sense. Good catch! I love the AirLift system!

[@terrysnider266]

Really good info Thanks

[@aurelianradu5234]

The left and right fan are the same/ fits ?

[@Manuqtix.Manuqtix]

Check for blown fuse? But what could cause the fuse to blow

[@kjeldmolvig5262]

Just learned that fans are not working. Are the relays inexpensive enough to just replace all 4 preemptively on a early Boxster and start from there?

[@BurnersCars]

I think the relays are pretty inexpensive, but I don't think I'd bother replacing them. As far as I can tell, it's almost always the fan or the ballast that comes with the fan. It's rare that the problem is with a relay.

[@MrJearley6]

Thank you for your help

[@rjeffrey1943]

Hi Burner, I'm having similar issues with a 1999 Boxster 986, 2.5ltr, has no A/c installed.The RH fan wont run when the engine heats up past normal temperature ( the LH side works perfectly fine ) I've replaced the ballast with one I borrowed and if I "jump" the ballast on 30+87 pins the RH fan comes on OK. so it would appear the fan works fine.I've checked all relays and they are fine, along with the C8/10 fuses.It seems strange that one side works fine with an increase in temperature but I'm wondering are there two sets of temp. sensors ?? one left and one right? I cannot think of anything else, the LH/RH fan runs OK when using the jump wires at the relay.Any help would be appreciated.Keep up the good work really enjoy the quality of your videos.Rob

[@BurnersCars]

Hi, Rob! KZbin marked this as spam for some reason (happens from time to time), so I missed it. Are you sure the relays are fine? If you jumped the relay and it works... that seems like the relay might be the problem.

[@vidyashankaraiyer4684]

My left radiator fan isn’t working at both speeds. I swapped all the relays back and forth and the right one always works but the left never works. I replaced the fan and the ballast, still doesn’t work. I then realized the fuse was blown, replaced that and still doesn’t work. Any idea what else I can check? Update 1: I shorted the top and bottom connectors on the relays. I can confirm the high speed works for the left fan and both speeds work on the right fan. Why doesn’t the low speed on the left fan work? I just replaced the fan and the ballast. Update 2: when I try jumping the relay in low speed, there is no spark or anything when I make the contacts.

[@soyabean911]

Did you get to the bottom of this one? That sounds like a strange one.

[@mbrunocondello]

Top Dad joke - ( Porsche fan )

[@Matias_sebastian]

Just quick question... Can anyone tell me how to remove the coolant tank? Mine crack

[@BurnersCars]

I haven't had to do this job, yet, so I can't give any personal advice, but Pelican Parts has a writeup that might help: www.pelicanparts.com/techarticles/Boxster_Tech/33-WATER-Coolant_Tank/33-WATER-Coolant_Tank.htm

[@theadvocate1925]

Both cooling fans failed on my 996 at 77,000 miles. Porsche purist: You're going to replacement them with OE German ones right? Me: The OE German ones both lasted less than 100,000 miles. These were designed and made by the same people that though it was a good idea to install the equivalent of a sealed wheel bearing inside a hot engine that is constantly bathed in hot engine oil. I'll take a chance with cheaper China made aftermarket. They'll probably last longer. Porsche purist: Don't think they will last even half as long as the German ones. Me: Think not? I have a 325CI BMW that I replaced the OE radiator fan with a China made aftermarket 6.5 years and 94,000 miles ago and it still kicks on every time. Not everything made in China is crap. And I don't think any Chinese engineer worth his\her degree would ever consider putting a self sealed wheel bearing inside a hot engine that is constantly bathed in hot engine oil. Porsche purist: No response.

[@chamixone]

I have the exact same side problem than you!

[@racekar80]

Wow, three jack stands in the background but you get under the car without using one!

[@BurnersCars]

Haha! Sharp eyes. In my defense, however, the 4th jack stand IS under the car 11:58

[@Baerchenization]

Foreign language fail - what is that part you could change in the alternative called exactly? I can't hear it out, even though you mentioned it 20 times... :P

[@BurnersCars]

No worries. You probably mean the ballast or resistor. part number 99661610100

[@Baerchenization]

Ahh ballast... thought I'm spazzing out here :) Thanks.

[@captlarry-3525]

damnest thing I ever saw !

[@natew.4699]

Dammit I laughed at 10 seconds in

[@jonjon738]

I like the videos and don't want to be insulting, but every sentence is not a question so don't raise the tone of the voice at the end. - thanks - LOL

[@9jfd1]

Are you serious??? Watch the video and learn a thing or too why even comment on someone's tone of voice, its completely irrelevant. Comments like this overshadow the essence of the technical knowledge. This is why I stay off social media idiots like you always find stupid condescending remarks. Are you perfect?

[@jonjon738]

@@9jfd1 Get a sense of humour you big ponce - A lot of Americans do it - I did after I'd lived in San Francisco for 5 years - it took months to wear off when I got back to England.

[@9jfd1]

@@jonjon738 Your comment is interpreted in many ways. You don't know me nor my ability to have a sense of humor. Who the fuck do you think you are? I couldn't care less where you live, keep negative comments to yourself.