In this video I have a look at a Honda 3 relay cooling fan system. It is a very common way to use two fans with no resistor all while having a high and a low speed option. They are pretty reliable but like anything have their faults. Let's see what is wrong with this one. -Enjoy!
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50 thoughts on “Honda odyssey : one cooling fan works on high / both work on low?”
  1. Avataaar/Circle Created with python_avatars Megan Gifford says:

    This is so helpful. I'm working on a 2014 Odyssey EX-L with the same setup. Appreciate the wiring diagram help. I've figured out that there is no power coming to the a/c fan relay (the other two for the radiator fan and compressor are fine). Of course, that fan doesn't spin. I'm not sure how to troubleshoot no power in the fuse box for that relay (already replaced the two 30amp and 7.5amp clutch fuses just in case). Help a sister out:)

  2. Avataaar/Circle Created with python_avatars Russell Andela says:

    Actually Eric, the stroopwafels are Dutch rather than English. I know this because my family are from Holland

  3. Avataaar/Circle Created with python_avatars Common Sense says:

    Excellent instruction on the fan wiring and how it works! You missed your calling as a teacher.

  4. Avataaar/Circle Created with python_avatars 407ForRent says:

    My driver side won’t run on a high. help!

  5. Avataaar/Circle Created with python_avatars 407ForRent says:

    Where did you get the wires are use them to remove the fuses?

  6. Avataaar/Circle Created with python_avatars mjfollrd says:

    Most excellent video and from now on I’ll make sure both fans operate in high and low speed mode after servicing A/C Thanks

  7. Avataaar/Circle Created with python_avatars John E. Carr says:

    Another great video.

  8. Avataaar/Circle Created with python_avatars Keith Hiebert says:

    This video helped me understand the overheating problem with my daughters 2007 Odyssey, same issue as this van. No one could figure it out! One fan only on high speed. Broken ground wire! That's 2 vehicle you've helped me with, Thanks again!

  9. Avataaar/Circle Created with python_avatars Tony Abrams says:

    Hi Eric I also have been a Fan Im Having Trouble with flowing the Low speed Drawing with you As Im following As you come to the first Relay you Draw Through the First Relay in it"s Natural State On it"s way to Ground But both Relay"s Control are On the same Power Source Which will Pull Both Wiper AT the Same time And The Power Flow Would be In another Direction Please HELP ME TO UNDERSTAND THIS

  10. Avataaar/Circle Created with python_avatars George Bell says:

    You make it look easy, good job!

  11. Avataaar/Circle Created with python_avatars jared398jkr says:

    Awesome video, was having the exact same issue as you were here so this helped me a lot!! Thanks!!

  12. Avataaar/Circle Created with python_avatars Retired Chief says:

    Thank you. You have a simple breakdown of the fan system that makes it easier to understand. I am trying to troubleshoot a 2004 Buick Rendezvous cooling fan issue but don’t have the diagnostic tools to help me turn the fans on off. Wish we had an Eric O in our neighborhood.

  13. Avataaar/Circle Created with python_avatars m4gician says:

    So was the issue a blown 30amp fuse? The purple one?

  14. Avataaar/Circle Created with python_avatars mckoy lach says:

    Hello,my 2010 Honda Odyssey,has cooling fans running,even when the car is shut off. Could it be a short relay or a shorted coolant temp sensor ? Thanks

  15. Avataaar/Circle Created with python_avatars John Brhel says:

    I'm a short time subscriber and missed this one. You sir are OUTSTANDIG1

  16. Avataaar/Circle Created with python_avatars TrackHawk1 says:

    Erick I have a 2019 accord and just yesterday I got an overheating warning. Fans usually come on at 200 degrees F. But not today for the first time. Both Fans only come on when I turn on ac which is what I had to do to get home safely

  17. Avataaar/Circle Created with python_avatars Joshua Wood says:

    Thanks brother! Very good info, still trying to figure out an simalar issue on my 04 honda odyssey. Ac blows ice cold, cooling fan works, but the fan on passenger side in engine bay not turning on! Fan has been replaced recently. Fuses are good…

  18. Avataaar/Circle Created with python_avatars 407ForRent says:

    Where did you get the pliers you’re using to remove the fuses?

  19. Avataaar/Circle Created with python_avatars Robert Long says:

    Hi 👋 you use a schematic to explain you theory but we can't tell what your looking at. Maybe a larger copy of the schematic your viewing and drawing on would help us better. Keep up the good work I know filming is double the work load.

  20. Avataaar/Circle Created with python_avatars CRAPO2011 says:

    Having a similar issue on my 2002 ody fan is finicky.

  21. Avataaar/Circle Created with python_avatars Darin B. says:

    I learned a long time ago about fuses they are like everything else the can go bad (eventually blowing) not because the current rating was excessive but just because the metal used in it had an impurity it causes excessive heat and over time the fuses current handling drops and eventually gets to low to handle the surge current and POP GOES THE WEASEL … the samething can happen in wire as well especially if it runs right at the rated current handling ability… heat cycling is bad and it will eventually kill things … just check the current draw prior to putting in a new fuse … you can also put say a headlight lamp in series with the suspected circuit … the brighter the light the more current the circuit is drawing … full brightness would indicate a direct short … but a fan motor would be very bright but dim some as it gained speed … the light would save torching a jump wire too (wire insulation smells so good) right? It could have been debris that caused a momentary short (excessive current draw) the fan motor ISN'T drawing excessive current now … only about half of the fuse at start up … so I wouldn't say the fan motor is shorting out either (bad windings on the armature) anyway sometimes fuses are weak do to a defect so they can blow out… hope that helps in future electrical diagnostics

  22. Avataaar/Circle Created with python_avatars Buddy Harshaw says:

    Helped a lot man thank you

  23. Avataaar/Circle Created with python_avatars Bob Johnson says:

    Read the title, diagnose it in my head, never fails, got to watch the whole video.

  24. Avataaar/Circle Created with python_avatars sivaraj palanisamy says:

    Eric, have you ever worked with Dealer or you have learned everything with your father shop.

  25. Avataaar/Circle Created with python_avatars Doyle Redwine says:

    another exceptional video and explanation. Many thanks South Main Auto

  26. Avataaar/Circle Created with python_avatars Duane Donaldson says:

    Typically when the 2 fans shut off and they both take the same amount of time to stop rotating and the suspect fan does not stop too much quicker than the good fan, there is no problem with bearings, dragging internal parts, etc. As you mentioned, due to the accident the fuse may have blown in the past, the body shop fixed the broken wire but did not know how to test a 2-speed fan system so they did not know the fuse was actually blown. That is my story and I am sticking to it. Thanks for the great video and diagnostics for 2-speed cooling fans. (Hiding in there somewhere is a bare wire waiting to short out hehehehe)

    Would like to have seen you manually bypass certain relays to operate each fan independent based on your different speeds on your wire diagrams just to prove out the theory but that is extra free work for your viewers hehe.

  27. Avataaar/Circle Created with python_avatars alvin boreo says:

    Eww a honda

  28. Avataaar/Circle Created with python_avatars 407ForRent says:

    My driver side won’t run on high, I can’t figure it out and help would be appreciated.👍👍👍

  29. Avataaar/Circle Created with python_avatars 407ForRent says:

    Hey Eric mines doing the same thing but it’s the opposite fan any suggestions would be greatly appreciated!

  30. Avataaar/Circle Created with python_avatars Hudson Gothard says:

    "Meow"

  31. Avataaar/Circle Created with python_avatars bookerol says:

    I would think that earlier in the year, when you repaired the AC, the high fan may not have even come into play.
    I once had a problem Jeep that died occasionally. Can't remember which fuse, but it used that same type of fuse and had a fracture in the internal conductor. Vibration, whatever, once in a while it would open and the engine would die, but restart eventually. In your case with high current, a cracked fuse would burn out and open permanently. Just a thought.

  32. Avataaar/Circle Created with python_avatars salvadorduran1 says:

    Hello Eric. what is the name of your diagnosis machine that you have in the video?

  33. Avataaar/Circle Created with python_avatars Bat Man says:

    I drive a 2009 Honda Oddy with same issues. (10 Years old!) Traffic Sucks, When I get cruising its blows cold. Drivers side warm passengers side cool.
    Changed the fuse as well. No change.
    Hope you fix it and let everyone know how this was done!

  34. Avataaar/Circle Created with python_avatars Master Chief 00117 says:

    Them Diaguns V are worth ever dollar. They are fast. Cover lots of cars. Do ABS cycling. etc.. All for $550.00

  35. Avataaar/Circle Created with python_avatars Dunc Keroo says:

    When you hear a cat under the hood; check the fuses 🙂

  36. Avataaar/Circle Created with python_avatars Drew Murphy says:

    What is the brand and name of the diagnostic tool you were using for the bidirectional testing

  37. Avataaar/Circle Created with python_avatars Jesse W says:

    Your explanation of the wiring diagram was great. I think a lot of people are intimated by electrical work because they don't have a solid understanding of electricity and how to read diagrams. As an engineer I've had a lot of practice but I still enjoyed seeing you work out the logic here

  38. Avataaar/Circle Created with python_avatars Buff Barnaby says:

    A stroopwafel is a wafer made from two thin layers of baked dough with a caramel syrup filling in the middle. Stroopwafels are popular in the Netherlands, and were first made in the Dutch city of Gouda. Nowadays the waffles are eaten worldwide

  39. Avataaar/Circle Created with python_avatars Danny says:

    Mines is a 2000 honda odyssey 3.5 liter v6 the ac fan works but the cooling fan dont ik honda boths fans are suppose to come on together to cool engine down right now my engine has an over heat and p0117 code change the ect sensor and i have a 5 volt reference HELP in your video the cooling fan comes right back on mines not

  40. Avataaar/Circle Created with python_avatars Pavel dalesssandro says:

    I know have to fix it kick it lol 😃😁

  41. Avataaar/Circle Created with python_avatars Simply Diagnostics says:

    Awesome walk through mate ⭐⭐⭐⭐⭐

  42. Avataaar/Circle Created with python_avatars Junk From Work says:

    I seriously love watching the process unfolding, it's funny you work through a problem one at a time at work and never see the process layed out.

  43. Avataaar/Circle Created with python_avatars bdrrogers says:

    Possible that the fuse blew during or after the collision because of some collision-related problem. Once the bangs were fixed, no further issue.