Dell Alert! Previous Fan Failure

Discussion in 'Tips, Tricks, and Tweaks' started by mairving, Aug 8, 2005.

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  1. mairving


    Jul 10, 1999
    Arlington, TN
    Been working on this one for a little bit. I had to replace a fan in a Dell Inspiron 2400 Desktop. The fan had a lead that had come loose. After I installed the new fan the message Alert! Previous Fan Failure would show on the screen. Options were to Press F1 to continue, Press F2 to continue. The system would boot but the annoying message would display.

    Things that didn't work:
    • Going into the BIOS and clearing the system log
    • Upgrading the BIOS
    • Removing the CMOS battery to reset BIOS
    • While in BIOS, turn on Num Lock, Scroll Lock and Cap lock and press Alt-E followed by Alt-B.
    • Prayer
    • Cussing
    • Physically Abusing computer

    Thing that did work:
    • Reversing the leads on the fan connector to the Motherboard
  2. Byte 2.0

    Byte 2.0

    Aug 15, 1999
    Secret City (Oak Ridge, TN)
    My favorite on a Dell is, the case has previously been removed. However it can be corrected in the Bios.

    I have seen that message you post before on many dells, however I was not allowed in those cases.
  3. AndyM


    Aug 22, 1999
    Rockford, IL
    I had an interesting experience with a Dell Dimension 4700. It wouldn't POST. No video activity. Fans on power supply would spin for part of a second and that was it. Trouble lights flashed indicating power supply failure. Fortunately it was under warranty. Technician arrived with new power supply, that didn't fix it. He came back with a new motherboard, and that didn't fix it. Then he came back with a fan, and voila! all systems go.
  4. bmwbykrydr


    Dec 12, 2005
    Alert! Previous Fan Failure solution.

    I was having the same error, but my situation was different. I was trying to install a bigger fan in my mother's Dell 4600c as the scroll fan was not moving enough air, in my opinion, and the HD and CPU were getting very hot. All of the solutions I had found were for replacing the fan or putting a bigger one in place of the CPU fan. I'm not going to use the CPU fan plug or fan at all so I had to find a different solution for the alert message.

    After spending all the time it takes to locate, drill, cut and install the huge fan, I turned it on for the first time and got the alert message. I spent a good hour or more on-line looking for a solution, but none of them worked. I did not have a fan go out, I removed one. I couldn't even find a schematic for the fan leads.

    So, I took a guess and figured that the white wire must be some kind of feedback loop for fan speed or temperature or something. When the fan is unplugged, the voltage between the black and white leads in the plug on the board was 4.84VDC. When I plug the fan in and test between the same leads that voltage dropped to 0.62VDC. So, I knew this was a feedback loop of some kind. With the fan unplugged from the board I measured the resistance between the black and white leads, which came out to 114 ohms. I took a 100 ohm and 15 ohm resister in series, clipped them to the leads in the plug on the board and started up the PC. It started up fine without the alert message.

    Since I'm not going to us the fan, I cut the plug off, pulled the red lead out, soldered the resisters to the white and black wire leads, put shrink wrap around the whole thing and plugged it in to the board. Everything works like a charm.

    You will have to ohm your fan to make sure you have the right resistance as I'm sure this number varies with other manufacturers. If you have a bad fan then the resistance you get may not be what you want to put in the plug, as that resistance is what set off the alert message in the first place. I have no information as to what range of resistance will work, but it would make sense that almost any should, making about .5VDC across the leads. The presence of a closed circuit, full 5VDC across the leads, probably sets off the alert message as well as an open circuit, 0VDC across the leads, but I have not tested that.

    Good luck, hope this helps someone.

  5. SaborL


    Dec 14, 2006
    Previous Fan error

    I had the same error message on my dell dimension 3000 after I replaced the fan. Try this: When it says press F1 to continue, or F2 for setup, press F2. There should be something in the bios that says "Report keyboard errors". Use the arrow key to put it to "DO NOT report keyboard errors". That should remove the error message. It worked for me, let me know if it does for you too.
  6. newbuilder14

    newbuilder14 Not so new

    Aug 2, 2006
    Maryland, United States
    Did you try to connect the fan into the SAME EXACT connector you took it out of?
  7. Panama Red

    Panama Red If I'm not here, I may be cruisin'! Staff Member

    Apr 8, 2003
    near the left coast of Michigan
    Ahh, year old thread guys.
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