system fan and CPU thermal sensor failed diags

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system fan and CPU thermal sensor failed diags

  • My wife's Latitude CPx has been experiencing problems since we bought it used.
    These are the symptoms:
    o fan never seems to be on
    o bottom of laptop becomes very hot after 30 minutes
    o system may shut down unexpectedly if not using a/c power
    o sometimes on boot up, after Windows logo appears, the screen becomes nearly
    black

    I downloaded the diags and ran a few quick tests. Can someone help with the result
    codes? I tried for about 40 minutes searching the knowledge base and forums for explanation
    of these result codes.
    ----
    CPU Thermal Sensor - Temperature Range Test : Fail
    Result code: 3400-011A
    Msg: Temperature sensor out of range, temp=101C, min 20c, max 100c

    System Fan - Fan On/Off Test : Fail
    Result Code: 3300-011A
    Msg: Expected fan on high RPM. Detected fan RPM =0

    Battery and Charger : Pass
    ----
    So from this it seems the fan is never running and is not functioning at all. Does anyone have
    experience replacing or repairing the system fan? Could this be a BIOS issue or does this
    failure truly indicate that the problem is mechanical and that the fan needs to be replaced?

    I will run a full diagnostics tomorrow morning. The laptop was becoming extremely hot and I
    wanted to give it time to cool down.

    -Shane
  • Shane,

    Thank you for using the Dell Community Forum.

    Fan never seems to be on.
    This could be because of the fan and thermal cooling system failure error you are gettig.
    Try upgrading to the latest bios file.
    Dell Latitude CPxH.
    or
    Dell Latitude CPxJ.
    After upgrading the bios run the fan test again.
    If it still fails you need to replace your fan and thermal cooling assembly.
    CPxJ service manual.
    CPxH service manual..

    You can purchase the parts from Dell Spare Parts.
    Dell Spare Parts Phone# 800-372-3355 Ext:6-9937
    Part#...........Description:
    1191T...........Thermal Cooling Subassy includes fan, fan shroud and heatsink)

    Bottom of laptop becomes very hot after 30 minutes.
    Wheather the fan and thermal cooling assembly are working or not, this is normal.
    The bottom plastics of all Dell portable systems get very hot.
    Dell does not recommend that you place the portable system on your lap.
    The system should be placed on a level work surface.
    If you want to have the system on your lap, have something underneath it as well.

    System may shut down unexpectedly if not using a/c power.
    This sounds like your battery is just to old and is not holding a long enough charge.
    Try another battery if possible.

    Sometimes on boot up, after Windows logo appears, the screen becomes nearly
    black.

    Try downloading and installing the latest video drivers.
  • I would just replace the fan.  That is most likely the problem.  I have seen faulty feedback regarding the temps on Latitudes using their diags but since the fan actually failed to turn on I would replace that.  And,  as always, make sure the Bios is up to date.  Also just fyi, the fan is not always supposed to be on.  It should just come on when the Latitude reaches a certain temperature.
  • My old laptope Latitude CS 400XT has the same problem,  
    with the diagnos utility I can turn on/off cpu fan but in normale mode stay off
    I update bios with  LCS-A13.EXE
    the real problem is CPU Thermal Sensor  how can I fixit Hmm 
    I need PWA shematic digrame
    Diagnos result:
    CPU Thermal Sensor - Temperature Range Test                : Fail
    Result Code: 3400-011A
    Msg: Temperature sensor out of range, temp=0C, min=20C, max=100C.
    SMBIOS - Environment Information                           : 
    Device Number : 1
    Device Type : Fan
    Temperature Probe Handle : No Probe Provided
    Cooling Unit Group : 0
    Conversion Factor : 0
    Stored Status : Safe
    Present Status : N/A
    Current Fan Speed : N/A
    Max/Min Non-critical Threshold : N/A
    Max/Min Critical Threshold : N/A
    Device Number : 1
    Description : CPU Internal Temperature
    Location : Processor
    Stored Status : Safe
    Present Status : Safe
    Current Temperature : 0.000 degrees C
    Reference Reading : N/A
    Max/Min Non-critical Threshold : N/A
    Max/Min Critical Threshold : 81.000 degrees C / 0.000 degrees C
    Max/Min Non-recoverable Threshold: N/A
    Max/Min Temperature Readable : 127.0 degrees C / 0.0 degrees C
    Resolution : 1.000 degrees C
    Tolerance : +/-0.5 degrees C
    Accuracy : Unknown
    SMBIOS - Environment Information : Pass
    SMBIOS - System Information                                : 
    Device Number : 1
    Manufacturer : Dell Computer Corporation
    Product Name : Latitude CS 400XT
    Version : N/A
    Serial Number : RMV7L
    Wake-up Type : Power Switch
    Device Number : 1
    Manufacturer : Dell Computer Corporation
    Type of Chassis : Portable
    Chassis Lock : Not Present
    Version : N/A
    Serial Number : RMV7L
    Asset Tag Number : N/A
    Bootup State : Safe
    Power Supply State : Safe
    Thermal State : Safe
    Security State : None
    SMBIOS - System Information : Pass