Fan Always Running with Red Light On

Discussion in 'Mac Pro' started by sigeats, Aug 19, 2008.

  1. sigeats macrumors newbie

    Feb 11, 2008

    I have a dual 1.8 G5. Lately the machine decides to blast the upper fan, as well as turning on a red light inside the machine above the power button. So I've figured out that it's that stupid sensor on the back tab on the plastic door. If I jam a piece of paper inside I can get it to turn off. Problem is it kind of turns on and off now. In other words, sometimes the paper works, other times it doesn't. The little piece of tape on the tab looks fine, so I'm worried it's a faulty sensor.

    My question is, is there any way to just disable the sensor? I promise to always leave the plastic door in place! I just want to disconnect the sensor, or maybe there's some crazy unix terminal thing I can do to turn off the sensor? Anybody out there know if this is possible? Help! This fan is driving me nuts! Any info anyone has would be great. Thanks
  2. CHGraphicAudio macrumors newbie

    Jun 23, 2013
    Years later and I'm having the same issue. I've tried using extra paper and new reflective material but my G5 stays in the Red Light protect mode from the moment I hit the start button. I ran a hardware test and it's indicating an issue with Processor A but I wonder if that's a result of the protection mode.
    Of course the processor fans aren't going crazy it's the hard drive fan.

    Did you find any solution?

    I just replaced the main hard drive and reinstalled after a failure. I thought that I might have misplaced or damaged something but it's so easy to switch out - I've double checked and all the cables (including the leads from the sensor) look/feel secure.

    It runs great aside from this issue. I hate to can the ol girl over a dumb light and fan issue. (if that's really all this is)
  3. brand, Jun 23, 2013
    Last edited: Jun 23, 2013

    brand macrumors 601


    Oct 3, 2006
    If you looked at the OP's profile you would have found that he last posted in March of 2013 and has only posted 7 times since becoming a member in 2008. The odds are against you on getting a reply on a 5 year old thread.

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