Connect with us

Dead CPU fan - Can You ID this part?

Discussion in 'Troubleshooting and Repair' started by whiteoutage, Mar 19, 2019.

  1. whiteoutage

    whiteoutage

    25
    1
    Jul 20, 2017
    When I apply 9 volts to fan I get nothing. What looks like a green LED seams to have possibly blown (has an open circuit) ? Anyone know what this component is and could it be the problem? Fan spins freely by hand though it is very old and maybe could use some oil. There appears to be a circuit board under the cover -maybe to control fan speed.
     

    Attached Files:

  2. 73's de Edd

    73's de Edd

    2,558
    1,045
    Aug 21, 2015
    Thats a thermal sensor, sampling air over fan temperature and telling the internal motor control circitry when to kick into HIGH speed . . . . . and accordingly . . . when it can drop back down to normal speed.
    Also you may need near a full 12VDC on that fan for it to kick off..

    73's de Edd

    If I made wine out of raisins . . . would I have to wait for it to age ?
     
    Last edited: Mar 19, 2019
  3. whiteoutage

    whiteoutage

    25
    1
    Jul 20, 2017
    Doesn't work with 12 volts either. Also tried shorting the thermal sensor while applying voltages -still no love. Looks like more than one issue on the circuit board - I take it that this thermal sensor should not be open like it is? Also wondering where I can source a comparable sensor cheaply?
     
  4. Bluejets

    Bluejets

    3,288
    652
    Oct 5, 2014
    Pretty hefty fan at 0.85A.
    Are you sure your power supply is up to the task..??
     
  5. 73's de Edd

    73's de Edd

    2,558
    1,045
    Aug 21, 2015
    I take it that this thermal sensor should not be open like it is?
    I have seen some sensors actually being 100K ohms resistance . . . . . so that one might be in the same catagory . . . but you would be able to see the resistance shift as heated with a blow drier.
     
  6. davenn

    davenn Moderator

    13,139
    1,704
    Sep 5, 2009

    why bother ?? a replacement fan is dirt cheap :)
     
  7. whiteoutage

    whiteoutage

    25
    1
    Jul 20, 2017
    Just to follow up, replacement is the solution. The board can not be remove AFAIK -the serrated bushing is press fit to the board in flimsy plastic making it nearly impossible to remove (possibly heating/softening encasing plastic then pulling it after de-soldering 3 stater leads -forget it!). Failure was a component, three legged variety, that got fried along with aforementioned sensor. Exact replacement on eBay for $9 did the business.
     
    Last edited: Mar 27, 2019
    Ian likes this.
Ask a Question
Want to reply to this thread or ask your own question?
You'll need to choose a username for the site, which only take a couple of moments (here). After that, you can post your question and our members will help you out.
Electronics Point Logo
Continue to site
Quote of the day

-