Announcement

Collapse
No announcement yet.

Dell latitude. Getting above 80C cpu fan not working.

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

    Dell latitude. Getting above 80C cpu fan not working.

    Hi
    I have dell latitude 7480. The laptop works but the cpu fan doesn't spin. So it gets very hot. Using hw monitor software I saw it was reaching 87C so I shut it off.
    However, just before it completely shut off the fan spin 1 sec. So i ran dell system diagnosis. Surprisingly the fan pass the test and was spining during diagnosing it.
    So I am suspecting the cpu thermistor but I don't know is which chip I should check. So I am asking for your help.
    Last edited by Weelcup; 12-12-2018, 12:29 AM.

    #2
    Re: Dell latitude. Getting above 80C cpu fan not working.

    Flash the bios and ec . The september bios update has
    - Updated Thermal Algorithm for performance.
    - Updated Embedded Controller Engine Firmware.
    - Updated Power Delivery Firmware.
    All donations to badcaps are welcome, click on this link to donate. Thanks to all supporters

    Comment


      #3
      Re: Dell latitude. Getting above 80C cpu fan not working.

      Originally posted by SMDFlea View Post
      Flash the bios and ec . The september bios update has
      - Updated Thermal Algorithm for performance.
      - Updated Embedded Controller Engine Firmware.
      - Updated Power Delivery Firmware.
      I will. I am waiting its new battery to arrive. as old battery is faulty.
      in order for the software to allow me to flash the bios...

      thanks for your advice...

      but any idea if the cpu thermistor sensor is embeded with the cpu or a separated chip on the motherboard.. ?

      Comment


        #4
        Re: Dell latitude. Getting above 80C cpu fan not working.

        "but any idea if the cpu thermistor sensor is embeded with the cpu or a separated chip on the motherboard.. ?"

        I don`t know.It does seem to be a uefi or EC issue though as you ran the fan test without problems .
        All donations to badcaps are welcome, click on this link to donate. Thanks to all supporters

        Comment


          #5
          Re: Dell latitude. Getting above 80C cpu fan not working.

          Originally posted by SMDFlea View Post
          "but any idea if the cpu thermistor sensor is embeded with the cpu or a separated chip on the motherboard.. ?"

          I don`t know.It does seem to be a uefi or EC issue though as you ran the fan test without problems .
          thanks for following up..
          during the past couple of days I went through plenty of issues regarding thermal/fan/heating and similar problems.

          the fan seems to run on the following mechanism:
          there are thermal sensors planted in or near CPU, GPU, Ram. these sensors measure the temp only. so as much as you have the correct readings of the temperature in the bios or any other software that monitor the temperature of the motherboard then the sensors are working correctly.
          the next stage is that these reading passes thermal Diodes which direct the signal to the bios and the bios is responsible of generating the right signal to the CPU to either operate or stop the fan from working.

          so in my case I totally agree with you @SMDFlea. the bios is the main responsible of the fault. I have already updated the bios with sep2018 bios version. but nothing new. I will downgrade it and upgrade it again and see.


          but thanks for your advices. it did help.

          Comment


            #6
            Re: Dell latitude. Getting above 80C cpu fan not working.

            Interesting!try with a programmer merging your dumps with the new update both ec and main and a clean me.

            Comment


              #7
              Re: Dell latitude. Getting above 80C cpu fan not working.

              Originally posted by bachir2004 View Post
              Interesting!try with a programmer merging your dumps with the new update both ec and main and a clean me.
              I downgraded the bios to the oldest version, 2016 one. and then updated it to the latest one , oct 2018. and guess what?!
              the fan started working but at exactly 85C not even 80C and will keep spinning until 40C then stop. but yes that was interesting and something related to bios indeed.

              the good part is that the fan does not make a loud noise and the cpu cooldown fast. so I assume that the thermal cooling system is working well.


              I didn't use any dump files or clear me versions. but I think this result would satisfy me. but for sure it was something to do with bios. considering that the fan was passing dell system diagnosis software successfully.

              thanks

              Comment


                #8
                Re: Dell latitude. Getting above 80C cpu fan not working.

                i remember having this problem with acer third generation,but what i did was flashing a fresh dump with newer bios and clear me.happy you solved your problem.

                Comment


                  #9
                  Re: Dell latitude. Getting above 80C cpu fan not working.

                  Originally posted by bachir2004 View Post
                  i remember having this problem with acer third generation,but what i did was flashing a fresh dump with newer bios and clear me.happy you solved your problem.
                  thanks. bachir2004.. I just did not use any dumps files just to avoid missing the service tag of the motherboard that matches the one on its bottom cover..

                  Comment

                  Working...
                  X