In this video I have a look at a customers 2006 Chrysler Town and Country. The customer complaint is that the fan runs at random even after you turn the car off! Well that's no good. Let's have a look ad see if we can fix it.
If an SMA Video has helped you out please consider giving using "Patreon" to help support us. The videos take real time to create and pull us away from real work that pays our bills. CLICK HERE:
CHECK OUT OUR "SMA SWAG" STORE! Go on Teespring and get your very own SMA merch!
If you don't like Patreon feel free to use the "PayPal Me" link:
The South Main Auto Amazon Store:
AES Wave Automotive Diagnostic Tools:
Thank you for all the continuing support!
--Eric & Vanessa O.
Feel like sending some swag to SMA because you love the videos but don't know where to send it?
Just ship it here:
South Main Auto Repair
47 S. Main St
PO Box 471
Avoca, NY 14809
Due to factors beyond the control of South Main Auto Repair, it cannot guarantee against unauthorized modifications of this information, or improper use of this information. South Main Auto Repair assumes no liability for property damage or injury incurred as a result of any of the information contained in this video. South Main Auto Repair recommends safe practices when working with power tools, automotive lifts, lifting tools, jack stands, electrical equipment, blunt instruments, chemicals, lubricants, or any other tools or equipment seen or implied in this video. Due to factors beyond the control of South Main Auto Repair, no information contained in this video shall create any express or implied warranty or guarantee of any particular result. Any injury, damage or loss that may result from improper use of these tools, equipment, or the information contained.

I Think it's possessed folks. uh 06 Town and Country guy just dropped it off to his engine won't shut off, but these cooling fans just make the fuse out for them here. So far, what's going on? I assume there's a relay stuck I don't know if they're built into the tip them on these or I'm pretty sure they're separate but I had this out and then I stuck the fuse back in it and it was really going kind of Haywire But at any rate, we'll leave that out. We'll go do some looking to see what this thing's made out of and the reason the guy thought his engine was still running is because he's deaf.

So everybody kept telling them like hey, you know your car's on and he's showing them the keys I got the keys but uh, at any rate, he said he stuck his hand on the car and he told me that the engine's still running but he has the keys. but indeed, it's just the fan that's running, not the engine. So anyhow, so I'd catch you up on that. Well let's see if we can find this little fella.

I'm assuming it's a relay that's stuck on. Nothing else in the car seems to be acting funny haha funny or otherwise, there's that one man that's Phillips head screws here too. It looks like these little guys thank you All right there's that looks like a couple push Clips there. The relay kind of hides down here in front of the car and that's a car anyways.

I Suppose we could be jumping the gun going for it, but it's about the only thing that makes sense. No engine light or anything. so I doubt the control side of it shorted there. She is.

okay. let's put the fuse back in here see if it takes off on us. Great thick snow. all of a sudden.

Relay cooled down a little bit. Nope. I can hear it. Foreign fans are getting all jittery right now.

Come on baby. they're winding up. They're winding down. They almost got going I'm making some funny noises here.

Let me take the Power of Two And from it here. Ghost Rider Well let me show you where this relay lives anyhow. see if it starts acting up on us. It was there for a second.

Oh every time I look at them, they keep tweaking. Let me show you. Well, never mind. I Went to show you and they kicked on.

Um, well let me show you where the three lane lives before. I unplug it. So that's where it lived. right there.

It's all about by that ribbon. Gotta get the red clip out of it here. Oh there we go. Didn't unplug it I Just took it on the connector here.

There we go. So the connector is unplugged. Nice and clean. Clean and green.

Obviously we know the wiring from there out is good and I'll be honest with you folks. I've seen this a dozen times. It's always a relay. No sense of playing dumb.

Uh, what? we could do or what we could have done to prove it to you is we come on the control side and we make sure the signal is not being sent to turn the relay on. Typically, we unplug these and they're usually all corroded and relays all gone funky. Um, I'm just going to do this one 100 based off experience 100 Parts Cannon Diagnosis: I'm going to get a cooling fan relay for it. We're going to put it in there because it's Friday and it's almost quitting time and if I'm wrong, well I'll just I'll eat it well.
Knapper didn't have one. Uh, Fast Freddy does though. they're bringing one up. So if you're working on one of these, so these are pretty simple relay, one of these wires is going to be power and one of these is going to the fan.

so you can, you know, check your fan assembly by using a jumper wire and just jumping these two they should. It should turn fans on theoretically and high or catching on. fire control side of the relay, we have the control. I Assume it's pulse width modulated would be my assumption and then one of those wires is going to be a ground.

I Assume probably the black one. Let's see if one of these is one of these is powered here. All right. So that's our full-time power in that one goes to our fan and I'm going to assume our black one here yeah, is the ground and then our other one here is going to be the control that turns this relay on.

We can plug our little U-scope into the back of it, use the scan tool and command the fan on, and we should be able to see that signal. So if that's something you're interested in I don't know if they are or not so we can look at that. Perhaps when we get the new relay, we'll plug it in here and then probe it just so you can see what it's supposed to look like and whatnot. Foreign there.

That's it. Kind of hard to hold the camera and not a cut off wheel at the same time. Don't touch your AC condenser or cut through the bumper cover or anything like that. You can always stick a bar under it and just snap it off too and then you know and then grind your rivet off and then you can.

You know, just we'll mount it back there. or if it comes with rivet or not. Looks like those big window regulator rivets. All right.

Fast Freddy Showed up. It's a classic. Uh, Romeo Yankee 446. foreign.

Hooked up. We'll get our connector here. plug it in I Went upstairs and got some rivet too. Even looks like the right size.

Let's make sure that we've plugged in the fuse I think we did. I don't even look I Put the cover back on it so it must be I did. All right. So let's get this thing decoded here.

We'll make sure everybody's happy first before we go. put it back in and then I can show you how the control side of it works. Okay, let's see. we're gonna go active tests and then we're gonna go radiator fan control.

Do we want live stream? Sure. I'll pick out some data pits here. I'll bust out the old youth scope here. a couple of probes.

They're kind of a big connector. We should build a probe in there. no problem see I'm just going to go into control side so the black is green and bare ground. If you're coming on a Chrysler kind of a loose connector and there's our control.
Hopefully we're probed in there. we'll hit start. so in this case it is because we're at 100 percent. it's not.

Um, let's see here. Let me change the time on our screen here. Got to get some stuff packed and back. Oh I keep hitting this button up top like what the heck is going on here.

So in this case it's not pulse width modulated. it's just pulled from 12 volts to ground when we start it. So all right, so let me see if there's a low speed or something that you can see the actuator actually or the pulse width modulation actually working here. Yeah.

So if I go to fan relay fan relay controller low speed fan relay the only one that works is the fan relay control altel is really awful on Old Chrysler So like say pre 2007 Chryslers It's probably the worst tool you can choose in in that regards. The the data lists are usually kind of hit or miss. You can get some erroneous data and a lot of the actuator tests are are irrelevant. They just don't even apply to the car you're working on.

So I guess the only thing we can do? let's just get it done. Let's just put it in and we'll boil it down and then I guess we could, uh, you know, back probe it and start it and see all that. But essentially what you would see during low speed is a pulse width modulated signal to the relay. Um I guess that's the best I can explain it to you.

The other thing you guys can do too if you didn't have a uh, if you don't have that little U-scope or a you know lab scope of any sort. to see a signal like that, you could use a really low current test light like an LED one. or you know, 100 milliamp, you know, test light like the little OTC one with a red light on it that would work good and then you could look to see if it's receiving this signal to turn on. Of course, if you don't have a scan tool to turn it on, you'd have to wait.

You know, until the vehicle is up to temperature and it was commanding the fan on. Or if the air conditioner worked on your car. you know you could turn the AC on and wait a little bit. You know to get that uh signal to turn it on this car.

the AC doesn't work so I can't even can't even really show you here. You know we'd have to wait for it to heat up and see it, wait for it to command to low speed which has got quite wants his car back here so we'll uh, throw the parts and pieces back on it and ship it, move on to something else. Actually, it's the last one last car for the day. So right, it wasn't even planned.

he just happened to be driving by. tell me his woes. Oh baby. Well that's it for all you mother butthole man.

freaking window all right. Eat junk cars. Nothing frustrates me worse than a stinking stupid electric power window and your customer doesn't tell you it's broke. but it's the number one rule in the aftermarket automotive shop.
Warning world has never ever touched a customer's window because they're always freaking broke because they're junk there. End of rant: Oh gosh, it pisses me off though at anyhow. at any rate, that's uh, fixing your cooling fan that stays stuck on on your Chrysler or maybe perhaps even in your case, one that doesn't work. Typically if the cooling fan relay fails, there's a wiring or circuitry problem.

We'll say on the control side you would have a check engine light and I would assume like a P Zero Four or something. maybe like a 481 451. something like that, some kind of cooling fan relay control circuit code. whatever that code is and then you know you would trace it down from there.

But our circuit was intact. It's just the relay was going. you know, whoopty on the inside, so that's it. Um, I'm glad we got the window up.

and why don't you guys get on that comment section. Tell me what's up. Questions, comments, concerns, insty the Facebook. You guys know where I'm at.

Just remember viewers, if I can do it, you can do it. Thanks for watching.

99 thoughts on “Possessed cooling fan in a caravan – mind of its own”
  1. Avataaar/Circle Created with python_avatars Richard Chivers says:

    Morning Eric, what 2as the name of the small hand held scope you where using, I know you said the name twice but I didn't catch it. Regards Richard 🇬🇧

  2. Avataaar/Circle Created with python_avatars lbouwkamp says:

    What was that tool you used to probe the signal circuit?

  3. Avataaar/Circle Created with python_avatars vacationism says:

    relax dude

  4. Avataaar/Circle Created with python_avatars Scotty Parker says:

    I have to admit you do get some Oddball things to fix keep up the good work Eric enjoy watching you work sir

  5. Avataaar/Circle Created with python_avatars David Smith says:


  6. Avataaar/Circle Created with python_avatars David Sawyer says:

    "Or catch on fire."

  7. Avataaar/Circle Created with python_avatars Kevin Berg says:

    I remember there was a time when this was such an incredibly common fault on Chryslers. I’ve replaced so many of these fan relays on all different kinds of Chryslers. The minivans and Grand Cherokee seemed the be the most common. Thankfully they’re external and generally easy to replace.

  8. Avataaar/Circle Created with python_avatars Simon Cutler says:

    “Fudge hole” will now be added to my curse word free working day 🤣

  9. Avataaar/Circle Created with python_avatars Steve Botnick says:

    Bummer the scope didn’t pan out, I really enjoy the advanced diag videos. With the economy crapping out, people trying to keep cars going longer and the cheap scopes available I think more of us will need the skills and techniques you graciously share. You are a gifted troubleshooter and it is much appreciated. re: the window, I once got trapped outside a possessed Chrystless product that auto locked the doors on me…vehicle running, late at night, in a remote location, my cell phone in the truck along with my jacket, me stuck outside wearing a hoodie at about -35f. Obviously survived and still have all my fingers. Putting windows down is now strongly ingrained for me.

  10. Avataaar/Circle Created with python_avatars Steve Duke says:


  11. Avataaar/Circle Created with python_avatars 88jopar says:

    You are one of the best automotive repair channels on YouTube!
    You are way better than SK, bc you show how to fix, repair, diagnose or repair vehicles from start to finish.
    Your methods are logical and you are an absolute treasure on YouTube.
    It seems Chrysler's most common issues, at least from the 2000's to early 2010's, are the wiring, certain electrical components such as the TIPM, transmission control solenoid, brakes and wheel bearings.
    Those are the most common issues I see you working on Chryslers of this era.
    Rarely do I see Chryslers coming in for engine, driveline or driveability issues in your shop.

  12. Avataaar/Circle Created with python_avatars repeatman says:

    "The power of Chrystler Compells you!"

  13. Avataaar/Circle Created with python_avatars Marc Carrier says:

    Lmao, loved watching Eric O. go nuts on a power window that doesn't go back up. Funny how we don't get informed of these things and we don't become aware of it till we're done and parking it back outside. I always make the same bleeping reaction! Love it!!! Lol

  14. Avataaar/Circle Created with python_avatars methanial73 says:

    I understand your frustration. I come from an electrical background, so I see these as common issues with all cars. You sh!t on Chrysler all day long, but my experience is they're some of the longest lasting cars out there and it's from experience.

  15. Avataaar/Circle Created with python_avatars Ian Hurford says:

    Great job as always Eric, what is the make of that little scope you used. Looks a very handy piece of kit.

  16. Avataaar/Circle Created with python_avatars AManWithManyDads says:

    What is the brand that makes that small scope you used?

  17. Avataaar/Circle Created with python_avatars Anyon Matt says:

    If he Says "negative ghost rider" one more time, I'm gonna poop on his porch

  18. Avataaar/Circle Created with python_avatars MechanicalCarnage says:

    Merry Chrysler to you and your family

  19. Avataaar/Circle Created with python_avatars Tom says:

    What brand is that LED bar light that you use? It seems nice and bright.

  20. Avataaar/Circle Created with python_avatars Mike S says:

    Are the fan bearings bad?

  21. Avataaar/Circle Created with python_avatars Nate Tallman says:

    Where's Josh going on vacation?

  22. Avataaar/Circle Created with python_avatars Michel Swerissen says:

    Its a Chrysler………….there all possessed at some stage………hammers and exorcism recommend.


  23. Avataaar/Circle Created with python_avatars Aymen Mohamed says:


  24. Avataaar/Circle Created with python_avatars Mike Barton says:

    PWM driving a relay?? Must be a solid state one then, and more of a motor speed controller?

    Thanks for the videos Eric, I watch every one.

  25. Avataaar/Circle Created with python_avatars Roger Chevelle says:

    Great diag Eric O. Had a friends parents that a caravan like that with the same issue.👍

  26. Avataaar/Circle Created with python_avatars Utah York says:

    "Mother fudge hole" – I'm using that one.

  27. Avataaar/Circle Created with python_avatars Ken DAVIS says:

    New Tech, Gotta Love it. Good to no where the Silly Relay Lives tho, and how it works. Nicely done once again E. O.

  28. Avataaar/Circle Created with python_avatars Vaughn Nottingham says:

    If it's not a Phillip's brand screw, then it's called a "crosshead" screw Mr. O.

  29. Avataaar/Circle Created with python_avatars gurubry says:

    I brought my Chevrolet into get serviced one time at a GM dealership… When I went to fill up gas after that service, the gas cap wouldn't lock and click anymore. I could only assume one of the service guys cranked on the gas cap really fast and hard and that broke the ratcheting.

    They ended up charging me for a new gas cap b/c there's no way to prove they broke it.

  30. Avataaar/Circle Created with python_avatars Cesar Barreiro, says:

    Eric what type work light are you using in this video TIA

  31. Avataaar/Circle Created with python_avatars Larry Bradshaw says:

    Checked your Amazon store but I don't see that nifty little scope. Got a link?

  32. Avataaar/Circle Created with python_avatars Pinoi_Cowboi says:

    pos windows..i feel ya!!

  33. Avataaar/Circle Created with python_avatars Dean Young says:

    First time seeing Eric get upset. He is human after all

  34. Avataaar/Circle Created with python_avatars asopw-_-uwu says:

    What dummy at dodge decided that was remotely a good place for a relay? 🤣

  35. Avataaar/Circle Created with python_avatars Mike Chiodetti says:

    Quick and out the door! Like an early 90's Ford F250 V8 gas engine with a stuck on fuel pump relay.
    Good one Mr.O!

  36. Avataaar/Circle Created with python_avatars Pinoi_Cowboi says:

    zzzzzzz hit the condenser..!!

  37. Avataaar/Circle Created with python_avatars Bart Goins says:

    To me, the best part of watching your videos is I get to learn something in nearly every one of them. I like that you don't try to be a comedian throughout the video, and you are actually interested in teaching us DIYers something that can save us both time and money. "Thanks for watching," oops, I mean, "thanks for the lesson."

  38. Avataaar/Circle Created with python_avatars Duane Buck says:

    Had a 97 T&C that did the same exact thing with the fan relay. I was busy doing all the research I could before firing any parts at it and one of the guys I worked with told me about the relay being a known issue. It was, thankfully the problem!

  39. Avataaar/Circle Created with python_avatars Jamie Patterson says:

    Having a flow chart in your mind, plus experience, makes it look like magic when electrical problems happen by and are fixed without a lot of fuss.

    I've said it before that the majority of time in auto repair training class should be on the flow of electrons from control to the component(s) and diagnoses. Without knowing how power flows from control to component, a person is basically flying blind.

  40. Avataaar/Circle Created with python_avatars Alex MacLean says:

    The thing about the windows makes sense to me now. When I worked at a dealership, we always put the driver window down. It used to be not to take any chance that you would lock the keys in. These days most cars wont let you lock the keys inside, but it's still just habit. Most of what we worked on was newer so there generally wasn't much chance of a window not working, but now that I work on junk, it makes a lot more sense lol